Head mounted displays (HMDs) with front facing cameras for transitioning between non-transparent modes and transparent modes

ABSTRACT

Systems and methods for executing content to be rendered on a screen of a head mounted display (HMD) are provided. One method includes executing the content to render interactive scenes on the screen and tracking an orientation direction of the HMD when worn on a head of a user and the interactive scenes are being rendered on the screen. The method includes changing view directions into the interactive scenes based on changes in the orientation direction of the HMD, such that movements of the head of the user causes the changes in the view directions into the interactive scenes. The method further includes receiving images of a real world space using a camera of the HMD. The camera of the HMD is configured to capture a location of real world objects in the real world space relative to the user of the HMD. The method includes detecting that at least one real world object is becoming proximate to the user of the HMD and generating a warning or message to be presented to the HMD, the warning or message indicating that the user is likely to bump or contact the at least one real world object. The method further includes transitioning at least a portion of the screen to a transparent mode. The transparent mode provides at least a partial view into the real world space using the camera of the HMD.

CLAIM OF PRIORITY

This is a continuation of U.S. patent application Ser. No. 16/027,199,filed on Jul. 3, 2018, and entitled, “Head Mounted Displays (HMDs) withFront Facing Cameras for Transitioning Between Non-Transparent Modes andTransparent Modes,” which is a continuation of U.S. patent applicationSer. No. 15/087,801, filed on Mar. 31, 2016, and entitled “Head MountedDisplays (HMDs) with Front Facing Cameras for Transitioning BetweenNon-Transparent Modes to Transparent Modes,” (since issued as U.S. Pat.No. 10,010,792 on Jul. 3, 2018), which is a continuation of U.S. patentapplication Ser. No. 14/254,881, filed on Apr. 16, 2014, and entitled“Systems and Methods for Transitioning between Transparent Mode andNon-Transparent Mode in a Head Mounted Display,” (since issued as U.S.Pat. No. 9,908,048 on Mar. 6, 2018) which claims priority under 35 USC119§ (e), to U.S. Provisional Patent Application No. 61/832,778, filedon Jun. 8, 2013, and entitled “SYSTEMS AND METHODS FOR TRANSITIONINGBETWEEN TRANSPARENT MODE AND NON-TRANSPARENT MODE IN A HEAD MOUNTEDDISPLAY,” which are incorporated herein by reference in their entirety.

FIELD OF THE INVENTION

The present invention relates to methods and systems for providingwarnings and notices to users of HMDs and modes for transitioning thescreen between a transparent mode and a non-transparent mode.

BACKGROUND

The video game industry has seen many changes over the years. Ascomputing power has expanded, developers of video games have likewisecreated game software that takes advantage of these increases incomputing power. To this end, video game developers have been codinggames that incorporate sophisticated operations and mathematics toproduce a very realistic game experience.

A number of gaming platforms have been developed and sold in the form ofgame consoles. A typical game console is designed to connect to amonitor (usually a television) and enable user interaction throughhandheld controllers. The game console is designed with specializedprocessing hardware, including a central processing unit (CPU), agraphics synthesizer for processing intensive graphics operations, avector unit for performing geometry transformations, and other gluehardware, software, and firmware. The game console is further designedwith an optical disc tray for receiving game compact discs for localplay through the game console. The game console is also designed foronline gaming, where a user can interactively play against or with otherusers over the Internet. As game complexity continues to intrigueplayers, game and hardware manufacturers have continued to innovate toenable additional interactivity and computer programs.

A growing trend in the computer gaming industry is to develop games andgame controllers that increase the interaction between user and thegaming system. The game controllers include features that enable richerinteractive experience by allowing a gaming system to track the player'svaried movements, and use these movements as inputs for a game executedon the gaming system.

It is in this context that embodiments of the invention arise.

SUMMARY

Embodiments of the present invention provide systems and methods fortransitioning from one transparent mode to another as described herein.

Broadly speaking, various embodiments of the invention disclose systemsand methods for executing a game presented on a screen of a head mounteddisplay (HMD). A game is executed and interactive scenes from the gameare rendered on a screen of the head mounted display. Images of the HMDworn by a user are received and are used to identify a first spatialposition of the HMD relative to a capture location that is directedtoward the user. Images of a controller held by the user are receivedand are used to identify a second spatial location of the controllerrelative to the capture location. The controller provides input to atleast partially drive interaction with the game being executed. Imagesthat identify a gaze direction of the user viewing the interactivescenes presented on the screen of the HMD, are received. Real-worldimages captured from a forward direction of the HMD are also received. Aportion of the screen is transitioned to a transparent mode such thatthe transparent mode replaces the interactive scenes rendered in theportion of the screen with at least part of the real-world images. Thetransparent mode is discontinued after a period of time so that the usercan continue to fully immerse in the game and fully experience the gameplay. The transition from non-transparent mode, where the user is fullyimmersed in the game, to a transparent mode enables a user to have apeek into the real-world without disrupting the user's game play. Thetransition also allows the user to gradually enter the real-world from ahighly intense game.

In one embodiment, a method is provided for executing content to berendered on a screen of a head mounted display (HMD). The methodincludes executing the content to render interactive scenes on thescreen. The screen is being operated in a non-transparent mode. Anorientation of the HMD worn on a head of a user, is tracked while theinteractive scenes are being rendered on the screen. Any changes in theorientation of the HMD causes a change in a view direction into theinteractive scenes that is being rendered on the screen. Images of areal world space is received from a pair of cameras of the HMD. Theimages are being captured while the interactive scenes are being rendredon the screen of the HMD. The pair of cameras of the HMD is configuredto capture three dimensional position of real world objects in relationto a location of the HMD in the real world space. The images of the realworld space captured by the pair of cameras of HMD are analyzed todetermine when the HMD is getting proximate to at least one real worldobject. In response to detecting the proximity of the HMD to the realworld object, a portion of the screen of the HMD is transitioned to atransparent mode so as to provide at least a partial view out to thereal world space in a directin of the at least one real world object.

In another embodiment, a method for executing an interactive game, isdisclosed. The method includes executing the interactive game. Theinteractive game is a multi-player game. In response to the execution ofthe game, interactive scenes of the interactive game are rendered on ascreen of a first HMD worn by a first user and a screen of a second HMDworn by a second user. The screens of the first HMD and the second HMDare being operated in a non-transparent mode. An action initiated by thefirst user is detected while the interactive scenes are being renderedon the screens of the first HMD and the second HMD. The action of thefirst user is directed to a region in a real-world environment in whichthe first and the second users are interacting with the interactivegame. The action is analyzed to identify an object in the region of thereal-world environment toward which the action is directed. The actionis analyzed using images of the real-world environment captured by oneor more image sensing devices available within the real-worldenvironment. A portion of the screen of the second HMD worn by thesecond user is transitioned from the non-transparent mode to atransparent mode, so as to provide a view of the object in the region,to the second user.

Other aspects of the invention will become apparent from the followingdetailed description, taken in conjunction with the accompanyingdrawings, illustrating by way of example the principles of embodimentsof the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the present invention may best be understood byreference to the following description taken in conjunction with theaccompanying drawings in which:

FIGS. 1A-1D illustrate different system architecture configuration of agame environment, in accordance with some embodiments of the presentinvention.

FIGS. 2A-2D illustrate components of head mounted display used in theinteraction with a game program, in accordance with embodiments of theinvention.

FIGS. 3A-3G illustrate implementation of transitioning between anon-transparent mode to a semi-transparent or fully transparent mode, insome embodiments of the invention.

FIGS. 4A-4E illustrate implementation of transitioning between anon-transparent mode to a transparent mode in three-dimensional spaceand the different transition regions within the head mounted display, insome embodiments of the invention.

FIG. 5 illustrates a method operation for executing a game presented ona screen of a head mounted display, in accordance with an embodiment ofthe invention.

FIG. 6 illustrates overall system architecture of a game module, in oneembodiment of the invention.

FIG. 7 illustrates a block diagram of a game system, in accordance withan embodiment of the invention.

DETAILED DESCRIPTION

Systems and methods for transitioning from a non-transparent mode to asemi-transparent or fully transparent mode within a head mounted display(HMD) are described. A game executing on a game console or game cloudcauses interactive scenes of the game to be rendered on a screen of theHMD. During execution of the game, an occurrence of a trigger event isdetected. In response to the detection of the trigger event, either aportion of the screen or the full screen of the HMD is transitioned froma non-transparent mode to semi-transparent or fully transparent mode.The transitioning allows presenting at least part of the real-worldimages captured from the vicinity of the HMD alongside the interactivescenes rendered in the portion of the HMD screen or to allow a user toview the real-world images from the vicinity of the HMD through thescreen.

In some embodiments, the transitioning to a semi-transparent modeincludes making the interactive scenes fade into the background whilerendering the real-world images in the foreground. In some embodiments,the transition may be done in gradual increments. In some embodiments,the transition in gradual increments may be linear or non-lineardepending on the game intensity. In some embodiments, the transitioningto a fully transparent mode includes replacing the interactive scenesrendering in the portion of the HMD screen with the real-world imagescaptured by a forward facing camera of the HMD. In other embodiments,the transition from non-transparent mode to fully-transparent mode iseffectuated by adjusting optic characteristics of the screen to make thescreen fully transparent. In some embodiments, the event may betriggered when a change in gaze direction of the user wearing the HMD isdetected. In some other embodiments, the event may be triggered when amovement is detected in the immediate real-world environment of theuser, such as a person entering a room where the user is playing thegame using the HMD, or sound is detected by the HMD within the immediatereal-world environment of the user, etc. In some embodiments, thetrigger event may be in response to a voice or motion command from theuser or a command issued from a controller or the HMD.

It should be noted that various embodiments described in the presentdisclosure may be practiced without some or all of these specificdetails. In other instances, well known process operations have not beendescribed in detail in order not to unnecessarily obscure variousembodiments described in the present disclosure.

In one embodiment, the system includes a computer, a hand-heldcontroller (HHC), and a head mounted display (HMD). In variousembodiments, the computer may be a general purpose computer, a specialpurpose computer, a gaming console, a mobile phone, a tablet device, orother such device which executes one or more portions of an interactiveprogram that is rendered on a display screen of the HMD. The interactiveprogram may be a multi-user game program that is played by multipleusers or a single user game program played by a user. In someembodiments, at least a portion of the game program is executing on thecomputer. In such embodiments, any remaining portions of the interactiveprogram are executed on a game cloud system, e.g., one or more virtualmachines (VMs). In some embodiments, all portions of the interactiveprogram are executed on the game cloud system.

The HMD is a display device, worn directly on a head of a user or aspart of a helmet. The HMD has a small display optic in front of one oreach eye of the user. In some embodiments, the HMD is capable ofreceiving and rendering video output from the program executing on thecomputer and/or on the game cloud system. A user operates a hand heldcontroller (HHC) and/or the HMD to generate one or more inputs that areprovided to the interactive program. In various embodiments, the HHCand/or the HMD communicates wirelessly with the computer, as thisprovides for greater freedom of movement of the HHC and/or the HMD thana wired connection. The HHC may include any of various features forproviding input to the interactive program, such as buttons, inertialsensors, trackable LED lights, touch screen, a joystick with inputcontrols, directional pad, trigger, touchpad, touchscreen, and may havecircuitry/logic to detect and interpret hand gestures, voice input orother types of input mechanisms. Furthermore, the HHC may be a motioncontroller that enables the user to interface with and provide input tothe interactive program by moving the controller.

Along similar lines, the HMD may include a user input circuit thatenables the user to interface with and provide input to the interactiveprogram by moving the HMD. Various technologies may be employed todetect the position and movement of the motion controller and/or theHMD. For example, the motion controller and/or the user input circuit ofthe HMD may include various types of inertial sensor circuits, such asaccelerometers, gyroscopes, and magnetometers. In some embodiments, themotion controller may include global position systems (GPS), compass,etc. In some embodiments, an accelerometer is a 6-axis low latencyaccelerometer. In some embodiments, the motion controller and/or theuser input circuit can include one or more fixed reference objects(otherwise termed “marker elements”), e.g., light emitting diodes(LEDs), colored points, light reflectors, etc. The images of the fixedreference objects are captured by one or more digital cameras of thesystem. In some embodiments, a digital camera includes a video camerathat further includes a single Charge Coupled Device (CCD), an LEDindicator, and hardware-based real-time data compression and encodingapparatus so that compressed video data may be transmitted in anappropriate format, such as an intra-image based motion picture expertgroup (MPEG) standard format. The position and movement of the motioncontroller and/or the HMD can then be determined through analysis of theimages captured by the one or more digital cameras.

FIG. 1A is an embodiment of an exemplary configuration of a system 100.In one embodiment, the system includes a game cloud 102, an HMD 104 andan HHC 106 communicating over the internet 110. In one embodiment, theHMD 104 includes a router (not shown) to communicate with the internet110. In some embodiments, the game cloud 102 is referred to herein as agame cloud system. The HMD 104 is placed by a user 108 on his head, suchthat the display screen(s) align in front of his/her eye(s), in asimilar manner in which the user 108 would put on a helmet. The HHC 106is held by the user 106 in his/her hands.

In various embodiments, instead of the HHC 106, hands of the user 108may be used to provide gestures, e.g., hand gestures, finger gestures,etc., that may be interpreted by interactive program and/or the logicwithin the HMD 104. In such embodiments, the user may wear aninteractive glove with sensors to provide tactile feedback. Theinteractive glove acts as the HHC, when worn by a user, and providesinput in the form of interactive gestures/actions to the interactiveprogram and/or the HMD. The interactive glove may include markerelements, such as LEDs, light reflectors, etc., to allow detection ofvarious movements. The interactive glove is one form of wearable devicethat is used to provide input to the HMD and/or the interactive programand that other forms of wearable clothing/device may also be engaged. Adigital camera 101 of the HMD 104 captures images of the gestures and aprocessor within the HMD 104 analyzes the gestures to determine whethera game displayed within the HMD 104 is affected. In one embodiment, thecamera 101 is an external digital camera located on a face plate 405 ofthe HMD 104 facing forward. In some embodiments, more than one externaldigital camera may be provided on the face plate of the HMD 104 tocapture different angles of the real-world images. In some embodiments,the camera may be stereo camera, an IR camera, a single-lens camera,etc. As used herein, the processor may be a microprocessor, aprogrammable logic device, an application specific integrated circuit,or a combination thereof.

The system 100 includes a network 110, which may be a local area network(LAN), a wide area network (WAN), or a combination thereof. Examples ofthe network 110 include the Internet, an Intranet, or a combinationthereof. In some embodiments, the network 110 uses a transmissioncontrol protocol (TCP)/Internet Protocol (IP) to communicate media datavia the network 110 between the game cloud 102 and the HMD 104 or theHHC 106. The embodiments are not restricted to the TCP/IP protocol butcan also engaged other forms of communication protocols forcommunicating media data via the network. In various embodiments, thenetwork uses a combination of Ethernet and TCP/IP to protocol tocommunicate media data via the network 110 between the game cloud 102and the HMD 104 or the HHC 106.

The game cloud 102 includes a coder/decoder (codec) 112 and a streambuffer 114. The stream buffer 114 stores a stream of media data 116,which is generated upon execution of a game program 117. The media data116 includes virtual environment data, virtual game object data, acombination thereof, etc. The virtual environment data is used togenerate a virtual environment of a game and the virtual game objectdata is used to generate one or more virtual game objects, e.g., virtualgame characters, virtual game objects, virtual points, virtual prizes,game interface, etc. The game program 117 is an example of theinteractive program executed by one or more servers of the game cloud102. The codec 112 uses a compressor/decompressor to code/decode mediadata using lossy compression, lossless compression, etc.

The HMD 104 is used to access an operating system (OS) that is executedby the processor of the HMD 104. For example, selection and activationof a button in the HMD 104 enables the processor of the HMD 104 toexecute the OS. Similarly, the HHC 106 may be used to access an OS thatis executed by the processor of the HHC 106. A button on the HHC 106 maybe used to have the processor of the HHC 106 to execute the OS.

In some embodiments, the OS allows the HMD 104 to directly access thenetwork 110. For example, a user may select a network access applicationthat is executed by the processor of the HMD 104 on top of the OS, usinga network access icon, a network access symbol, etc. The network accessapplication provides a list of networks from which to select a networkfor accessing the network 110. User authentication may be required toaccess the network 110, in accordance to network access protocol. Accessto the network 110 is enabled is enabled for the user upon selection andsuccessful user authentication (if needed). A built-in router (notshown) within the HMD 104 uses the network 110 to interact with the gamecloud to exchange game data. In these embodiments, the communicationbetween the network 110 and the HMD 104 follows a wireless communicationprotocol. Along similar lines, the HHC 106 gains access to the network110 by selecting the network using network access application and thecommunication between the HHC 106 and the network follows a wirelesscommunication protocol.

Once the network 110 is accessed, the OS allows the HMD 104 to accessthe game program 117 in a manner similar to the selection of thenetwork. For example, when the user 108 selects a game accessapplication executed by the processor of the HMD 104 on top of the OSthrough a game access icon, a game access symbol, etc., the game accessapplication requests access to the game program 117 via the processor ofthe HMD 104 for displaying to the user 108. Upon obtaining access to thegame program 117, a microcontroller of the HMD 104 displays the game ona display screen of the HMD 104. In some embodiments, the display screenof the HMD 104 is a high performance screen to reduce blur when the HMD104 is moved rapidly. In one embodiment, the display screen is a LiquidCrystal Display (LCD) screen. The user 108 performs one or more headand/or eye motions, e.g., head tilting, winking, gazing, shifting gaze,staring, etc., and each head or eye motion triggers the user inputcircuit to generate an input, which may be used to play the game. Inthese embodiments, the game program 117 executes on the game cloud 102and the communication between the game program 117 and the HMD 104 isthrough the built-in router and the network 110.

In some embodiments, the game access application requests userauthentication information, such as a username and/or a password, fromthe user 108 to access the game program 117. Upon receiving successfulauthentication from the game cloud 102, the game access applicationallows access of the game program 117 to the user 108.

In various embodiments, instead of accessing the gameapplication/program, the user 108 requests access to a web page uponaccessing the network 110 and the web page allows the user 108 to accessthe game program 117. For example, the user 108 selects a web browserapplication via the user input circuit or via the HHC 106 to access aweb page. Upon accessing the web page, the user 108 plays a gamedisplayed on the web page or accesses the game using a link providedwithin. The game is rendered when the game program 117 is executed onthe game cloud 102. In some embodiments, user authentication may berequired before providing access to the web page to play the game thatis displayed when the game program 117 is executed on the game cloud102. The username and/or the password is authenticated in a mannersimilar to that described above when the user 108 accesses a game viathe game access application.

When the game program 117 is accessed, the codec 112 encodes, e.g.,compresses, etc., a digital data stream of the media data 116 forsending a stream of encoded media data to the HMD 104 via the network110. In some embodiments, a digital data stream of the encoded mediadata is in the form of packets for sending via the network 110.

The HMD 104 receives the digital data stream of the encoded media datafor the selected game program via the network 110 from the codec 112 andthe digital data stream is processed, e.g., depacketized, decoded, etc.,and the processed stream is used to display a game on the display screenof the HMD 104. When a game data is displayed on the display screen ofthe HMD 104. An external camera 101 of the HMD 104 captures one or moreimages of a real-world environment in the immediate vicinity of the user108, in response to detection of a trigger event at the HMD. In someembodiments, the external camera 101 is a video camera. Examples of thereal-world environment include a room from where the user 108 isaccessing the game, a geographical region in which the user 108 islocated, real-world objects around the user 108, etc. Examples of ageographical region include a park, a road, a street, a lake, a city, alandmark, etc. Examples of a real-world object include a bus stand, acoffee shop, a store, an office, a vehicle, a room, a desk, a table, achair, a ball, etc. Real-world environment data, including one or moreimages of the real-world environment, in one embodiment, is processedand stored locally in the HMD and used for subsequent rendering on thescreen of the HMD. User input, such as a trigger event, may beprocessed, packetized and encoded by the HMD 104, and sent to the codec112 in the game cloud 102 through the built-in router and the network110. In some embodiments, in addition to the user input, the real-worldenvironment data may also be packetized and encoded by the HMD 104 andsent as a stream of encoded environment data via the built-in router ofthe HMD 104, the network 110 to the codec 112 in the game cloud 102.

Upon receiving the user input and/or the real-world environment data,the game program 117 generates additional media data that is packetizedby one or more servers of the game cloud 102 to generate a stream ofadditional media data. The additional media data may includemodifications to game play, including modifications to virtual gameobject, e.g., computer-generated object, etc., that is used for updatingthe virtual game environment rendered on the HMD. The stream ofadditional media data is stored in the stream buffer 114, encoded by thecodec 112, and sent as a stream of encoded additional media data via thenetwork 110 to the HMD 104. The HMD 104 receives the stream of encodedadditional media data, depacketizes the stream, and decodes the encodedadditional media data to provide the additional media data to themicrocontroller of the HMD 104. The microcontroller of the HMD 104changes a display of a game that is executed by the game program 117rendered on the screen of the HMD based on the additional media data.

User inputs may be provided through the HMD 104 and/or the HHC 106. Forexample, the user 108 may provide input using input interface/mechanismprovided in the HMD 104. Alternately, the user 108 may perform handmotions, e.g., press of a button, movement of a joystick, hand gesture,finger gesture, a combination thereof, etc., using the HHC and such userinput provided at the HHC 106 generates input data that is convertedinto input signals by a communications circuit of the HHC 106 forsending to a communications circuit of the HMD 104. Of course, the HHCincludes hand-held controllers, joysticks, motion controllers, wearablearticles of clothing, wearable devices, etc. The input signalsoriginating from the HHC 106 and the HMD 104 are converted from ananalog form to a digital form by the communications circuit of the HMD104, packetized, encoded by the HMD 104 and sent via the network 110 tothe codec 112. Examples of a communications circuit of the HMD include atransceiver, a transmit/receive circuitry, a network interfacecontroller, etc.

In some embodiments, the game program 117 maps input data that isgenerated by the HMD with input data that is generated at the HHC (fore.g., based on the hand motions) to determine whether to change a stateof a game that is displayed on the HMD 104. For example, when an inputfrom the HMD is received via the network 110 with an input generated atthe HHC 106, such as a press of a button on the HHC 106, the gameprogram 116 determines to change a state of a game. Otherwise, the gameprogram 117 determines not to change a state of a game.

Input data of the inputs generated based on the hand motions and/orhand-held controller motions are communicated by a communicationscircuit of the HHC 106, e.g., a transceiver, a transmit/receivecircuitry, etc., to a communications circuit, e.g., a transceiver, atransmit/receive circuitry, etc., of the HMD 104. Input datacommunicated to the HMD and/or input data generated by the HMD arepacketized and encoded by the HMD 104 and sent as a stream of encodedinput data via the network 110 to the codec 112. For example, the inputdata may be sent directly from the HMD 104 using the built-in router viathe network 110 to the game cloud 102. In a number of embodiments, theuser 108 performs the hand motions and provides user input from the HMDto change a location and/or orientation of the virtual object renderedat the HMD.

The codec 112 decodes, e.g., decompresses, etc., the stream of encodedinput data received via the network 110 from the HMD 104 and the decodedinput data is buffered in the stream buffer 114 for depacketizing andsending to the game program 117. One or more servers of the game cloud102 depacketizes the stream of decoded input data and sends the inputdata to the game program 117. Upon receiving the input data, the gameprogram 117 generates next media data that is packetized to generate astream of next media data by one or more servers of the game cloud 102.The stream of next media data is stored in the stream buffer 114,encoded by the codec 112, and sent as a stream of encoded next mediadata via the network 110 to the HMD 104. The HMD 104 receives the streamof encoded next media data, depacketizes the stream, and decodes theencoded next media data to provide the next media data to themicrocontroller of the HMD 104. The microcontroller of the HMD 104changes a display of a game that is executed by the game program 117based on the next media data. For example, the microcontroller changes alook, position, and/or orientation of the virtual game object that iseither overlaid on the one or more images of the real-world environmentor simply rendered on the screen of the HMD 104.

It should be noted that the input data generated at the HHC and/or theHMD changes a state of the game. In some embodiments, a display of agame is referred to herein as a portion of interactivity associated withthe game program 117.

In various embodiments, instead of communicating the input data that isgenerated based on the hand motions from the HHC 106 to the HMD 104, theinput data is communicated directly from the HHC 106 via the network 110to the codec 112. The input data that is generated at the HHC 106 iscommunicated by the HHC 106 in a manner similar to the communication bythe HMD 104. For example, the input data that is generated based on thehand motions from the HHC 106 is encoded and packetized by the HHC 106and sent as a stream of encoded input data via the network 110 to thecodec 112.

It should be noted that in the embodiment illustrated in FIG. 1A, theHMD and the HHC individually directly communicate with the network 110without going through a game console or an external router. In analternate embodiment, the HHC may communicate with the HMD to transmitthe input data generated at the HHC and the HMD may directly communicatethe data at the HHC and/or the HMD with the network 110. In both ofthese embodiments, media data 116, additional media data, the next data,etc., are streamlined directly to a wireless access card (WAC) of theHMD 104 by the codec 112 of the game cloud 102 via the network 101 andthe built-in router. Moreover, in these embodiments, data, e.g., inputdata, real-world environment data, etc., is streamed directly by the WACof the HMD 104 to the codec 112 of the game cloud 102 via the built-inrouter and the network 110. The WAC in conjunction with the built-inrouter of the HMD is able to transmit the streaming media data and theinput data to and from the HMD.

FIG. 1B is a diagram of an embodiment of a system 150 for transferringdata between the HMD 104 or the HHC 106 and the game cloud 102 via thenetwork 110 and a router 152. The system 150 is similar to the system100 (FIG. 1A) except that the system 150 includes the router 152 betweenthe HMD 104 and the network 110. The router 152 is also located betweenthe HHC 106 and the network 110. In this embodiment, the WAC of the HMD104 will interface with the router 152 to communicate with the network110.

The HMD 104 is coupled to the router 152 via a wireless connection,e.g., a Bluetooth connection or a Wi-Fi connection, etc. Moreover, theHHC 106 is coupled to the router 152 via a wireless connection. In someembodiments, the router 152 is coupled to the network 110 via a wiredconnection.

The system 150 illustrated in FIG. 1B operates in a similar manner tothat of the system 100 (FIG. 1A) except that a stream of encoded data issent from the HMD 104 or the HHC 106 to the router 152. The router 152routes, e.g., directs, etc., the stream of encoded data to a path in thenetwork 110 to facilitate sending the stream to the codec 112. Therouter 152 uses the IP address of the codec 112 to route the stream ofencoded data to the codec 112. In some embodiments, the router 152determines a network path of the network 110 based on network trafficfactor, e.g., packet traffic on the network path, congestion on thenetwork path, etc.

The router 152 receives a stream of encoded data from the game cloud 102via the network 110 and routes the stream of encoded data to the HMD104. For example, the router 152 routes the stream of encoded datareceived from the game cloud 102 via the network 110 to the HMD 104based on the IP address of the HMD 104. In some embodiments that use thesystems 100 and 150, the game execution occurs mostly on the game cloud102. In some embodiments, some part of the game may execute on the HMD104 while the remaining portions may execute on the game cloud 102.

FIG. 1C is diagram of an embodiment of a system 170 for using a computer172 for communicating media data to the network either directly orthrough the router 152.

In some embodiments, a list of wireless networks is rendered on thescreen of the HMD 104 for user selection. Alternately, in some otherembodiments, a list of wireless networks is presented on a displayscreen associated with the computer 172. For example, when the computer172 is a mobile phone, the mobile phone includes a display screen fordisplaying the list of wireless networks. As another example, when thecomputer 172 is coupled to a television display screen, the list ofwireless networks is displayed on the television display screen. Inthese embodiments, the list of wireless networks is accessed when theprocessor of the computer 172 executes the wireless access applicationstored within a memory device of the computer 172. The processor 176executes the wireless access application when the user 108 generatesinput data via the HMD 104 or the HHC 106 by performing the head motionsand/or hand motions. Input data generated based on the head motionsand/or the hand motions are sent from the communications circuit of theHMD 104 or the HHC 106 to the computer 172. When the processor of thecomputer 172 receives the input data, the wireless access application isexecuted to generate the list of wireless networks.

The computer 172 includes a network interface controller (NIC) 174 thatrequests a portion of the game program 117 from the game cloud 102.Examples of a NIC include a network interface card and a networkadapter. The portion of the game program 117 is encoded by the codec 112and streamed via the network 110 to the NIC 174 of the computer 172. Aprocessor 176 of the computer 172 executes the portion of the gameprogram 117 to generate media data, which is sent from a communicationscircuit 178, e.g., transceiver, Transmit/Receive circuit, a networkinterface controller, etc., of the computer 172, to the HMD 104 fordisplay on the display screen of the HMD 104. A communications circuitof the HMD 104 receives the media data from the computer 172 and sendsthe media data to the microcontroller of the HMD 104 for processing anddisplaying the media data on the display screen of the HMD 104.

Moreover, the communications circuit 178 of the computer 172 receivesinput data generated based on the head motions from the HMD 104 and/orthe hand motions from the HHC 106 and sends the input data to theprocessor 176. The input data, in one embodiment, may be real-worldenvironment data received from the communications circuit of the HMD104. The processor 176 executes the portion of the game program 117 thatis stored within the computer 172 to generate additional media data,which is sent from the communications circuit 178 to the communicationscircuit of the HMD 104. Before or after receiving the additional mediadata, input data from the HHD 104 and/or the HHC 106 that is generatedas part of the game play using head motions and/or the hand motions, issent by the communications circuit of the HMD 104 to the processor 176via the communications circuit 178. In response to the input data, theprocessor 176 executes the portion of the game program 117 that isstored within the computer 172 to generate the next media data, which issent from the communications circuit 178 to the communications circuitof the HMD 104. The next media data is sent to the communicationscircuit of the HMD 104 to change the game play, includingchanging/updating virtual game objects and/or virtual environment of agame displayed by execution of the game program 117. When the gameobjects, e.g., real world objects, virtual game objects, etc., and/orvirtual environment changes, a game state of the game displayed byexecution of the game program 117 changes.

In some embodiments, the game state is sent by the NIC 174 of thecomputer 172 via the router 152 and the network 110 to the game cloud102 to inform one or more servers of the game cloud of the current gamestate.

In various embodiments, media data 116, additional media data, nextmedia data, etc., are initially sent from the codec 112 via the network110 and the router 152 to the HMD 104 until a portion of the gameprogram 117 is downloaded to the computer 172 from the game cloud 102.For example, initially, the user 108 uses the game access application toaccess the game program 117. When the game program 117 is accessed, themedia data 116, the additional media data, the next media data, etc., issent from the codec 112 via the network 110 and the router 152 to theHMD 104 for display on the display screen of the HMD 104. During thetime of access of the media data from the game cloud 102 for display onthe HMD 104, the NIC 174 of the computer 172 downloads a portion of thegame program 117 from the game cloud 102 via the network 110 and therouter 152.

In some embodiments, when the game program 117 is accessed by thecomputer 172, media data, e.g., the media data 116, the additional mediadata, the next media data, etc., is sent from the codec 112 via thenetwork 110 directly to the HMD 104 for display on the display screen ofthe HMD 104 by bypassing the computer 172 while the computer accessesthe game program on the game cloud for downloading. The received mediadata is rendered on the display of the HMD 104. Meanwhile, the NIC 174of the computer 172 downloads a portion of the game program 117 from thegame cloud 102 via the network 110 and the router 152.

In a number of embodiments, a portion of input data generated based onthe head motions and/or hand motions and/or a portion of the real-worldenvironment data is sent from the HMD 104 via the router 152 and thenetwork 110 to the codec 112 of the game cloud 102 while the remainingportion of the input data and/or the remaining portion of the real-worldenvironment data is sent from the communications circuit of the HMD 104to the communications circuit 178 of the computer 172.

In various embodiments, a portion of input data generated based on thehand motions is sent from the communications circuit of the HHC 106 viathe router 152 and the network 110 to the codec 112 of the game cloud102 and the remaining portion of the input data is sent from thecommunications circuit of the HHC 106 to the communications circuit 178of the computer 172 either through the HMD or directly.

In various embodiments, media data, e.g., the media data 116, theadditional media data, the next media data, etc., that is generated byexecuting the game program 117 using the user input received from thecomputer/HMD/HHC, is sent from the codec 112 of the game cloud 102 viathe network 110 and the router 152 to the HMD 104 for rendering on thedisplay screen of the HMD 104 as part of game play and media data thatis generated by execution of the portion of the game program 117 by theprocessor 176 of the computer 172 is sent from the communicationscircuit 178 of the computer 172 to the HMD 104 for display on thedisplay screen. In these embodiments, the game cloud 102 and thecomputer 172 have synchronized game states. For example, the codec 112sends a game state generated by execution of the game program 117 viathe network 110 and the router 152 to the NIC 174 of the computer 172 toinform the computer 172 of the game state. As another example, the NIC174 of the computer 172 sends a game state generated by execution of theportion of game program 117 on the computer 172 via the router 152 andthe network 110 to the codec 112 of the game cloud 102 to inform the oneof more game cloud servers of the game state. The communication betweenthe codec 112 of the game cloud 102 and the NIC of the computer are doneperiodically to keep the game states synchronized on both sides.

In several embodiments, media data, e.g., the media data 116, theadditional media data, the next media data, etc., that is generated byexecuting the game program 117 and sent from the codec 112 of the gamecloud 102 to the HMD 104 has a higher amount of graphics than media datathat is generated by the processor 176 of the computer 172. As isevident, in some of the embodiments, the computer 172 is bypassed whenthe media data is directly sent from the codec 112 of the game cloud 102via the network 110 to the HMD 104.

FIG. 1D illustrates a system configuration where the HMD communicatesinput data and/or media data to/from the codec 112 using a computer 172and a router 152. The configuration of the system 190 is similar to theconfiguration of system 170 described with reference to FIG. 1C. Thesystem 190 includes a computer 172 that is communicatively connected tothe game cloud 102 through the router 152 and the internet 110 and isconfigured to obtain portions of the game program and game related data.The computer is also communicatively connected to the HMD 104 and theHHC 106 to obtain input data.

In some embodiments, a processor of the computer 172 executes a wirelessaccess application stored within a memory device of the computer 172 toaccess the network 110. In some embodiments, the wireless accessapplication is executed in response to input data received from a uservia the HMD 104 or the HHC 106. The input data may include head motionsand/or hand motions. When the processor of the computer 172 receives theinput data generated by the HMD or the HHC, the wireless accessapplication generates a list of available wireless networks from which anetwork is selected to access the network 110.

The computer 172 includes a network interface controller (NIC) 174 thatrequests a portion of the game program 117 from the game cloud 102 andin response, the portion 117-b of the game program 117 encoded by thecodec 112 is streamed via the network 110 to the NIC 174 of the computer172. In some embodiments, the game cloud includes a games database 131from which the game program 117 is retrieved and downloaded to thecomputer 172. In some embodiments, a portion 117-a of the game program117 is downloaded from the games database 131 on to the game server 102and the remaining portion 117-b of the game program 117 is downloaded tothe computer 172. In some embodiments, the portion 117-b that isdownloaded to the computer 172 is the entire game. The processor 176 ofthe computer 172 executes the portion 117-b of the game program 117 togenerate media data, additional media data and next media data(collectively termed ‘media data’) which is sent from a communicationscircuit 178, a network interface controller, etc., of the computer 172,to the HMD 104 for display on the display screen of the HMD 104.

The additional media data and next media data may be provided inresponse to input data, including head motions/other user input, handmotions, etc., received from the HMD 104. In addition to the headmotions and/or hand motions the input data, in one embodiment, may alsoinclude real-world environment data that is captured by an externalcamera 101 disposed on the outside face of the HMD 104 and transmittedby the communications circuit of the HMD 104. In some other embodiment,the real-world environment data captured by the external camera 101 isstored locally within the HMD and used in rendering on the HMD screen.The additional media data provides virtual environment related data forrendering the virtual game scenes on the HMD and the next media dataprovides changes to virtual game objects and/or virtual environmentdisplayed within the virtual game scenes during game play. Acommunications circuit of the HMD 104 receives the media data as a mediastream from the computer 172 and sends the media data to themicrocontroller of the HMD 104 for interpretation and display on thedisplay screen of the HMD 104. When the game objects, e.g., real gameobjects, virtual game objects, etc., and/or virtual environment changes,a game state of the game displayed by execution of the game program 117,changes.

As mentioned earlier, in some embodiments, the game state is sent by theNIC 174 of the computer 172 via the router 152 and the network 110 tothe game cloud 102 to inform one or more servers of the game cloud 102of the game state so as to synchronize the game state with the gamestate on the computer 172. In these embodiments, most of the gameexecution occurs on the computer 172.

In some embodiments, a portion 117-a of the game program 117 is executedon the game cloud 102 while the game program 117 is being downloaded onto the computer 172. Accordingly, media data associated with theexecution of the portion 117-a of the game program 117 on the game cloud102, are sent directly from the codec 112 via the network 110 and therouter 152 to the HMD 104 for rendering on the HMD until the portion117-b of the game program 117 is downloaded to the computer 172 from thegame cloud 102. In one embodiment, the portion 117-b of the game program117 is downloaded and stored in the local storage 113 of the computer172 and executed by the processor 176. Once the portion 117-b isdownloaded and the processor 176 of the computer 172 starts executingthe game portion 117-b, the media data will be transmitted from thecomputer 172 to the HMD 104 for the portion 117-b of the game program117. In some embodiments, all the media data for the game program aretransmitted directly from the computer 172 to the HMD 104 for rendering.The computer 172 may also periodically transmit the media data to thegame cloud 102 to synchronize the game state of the game program on thegame cloud 102 with the game state on the computer 172.

In a number of embodiments, a portion of input data based on the headmotions and/or hand motions are captured by an observation camera 171that is connected to the computer 172. In some embodiments, theconnection between the observation camera 171 and the computer 172 maybe a wired connection. In other embodiments, the connection between theobservation camera 171 and the computer 172 may be a wirelessconnection. In some embodiments, the observation camera 171 is any oneor combination of stereo camera, IR camera or mono-camera. In someembodiments the observation camera 171 is one of a video camera or astill-motion camera. The images captured by the observation camera 171may be used to determine the location and motion of the HMD and the HHC.For example, the images of the observation camera 171 may be used toidentify coordinates of position A for the HMD (X_(a), Y_(a), Z_(a)) andcoordinates of position B for the HHC (X_(b), Y_(b), Z_(b)). In additionto the coordinates of the coordinate plane, the images of theobservation camera may be used to determine the pitch, the yaw and theroll to generate the six-axis data for the HMD and HHC. In someembodiments, the head and/or hand motions generated at the HMD and theHHC are captured by the observation camera 171 and transmitted to themicrocontroller of the HMD 104 as six axis data. The six-axis data fromthe HMD 104 and/or HHC 106 are interpreted to generate the input data.The interpreted input data is transmitted from the HMD 104 to thecomputer 172 to influence the outcome of the game program. In someembodiments, the head and/or hand motions captured by the observationcamera 171 are directly transmitted to the processor 176 where it isinterpreted to generate the six-axis data. The observation camera 171observes the motions (head and/or hand) of the user and this informationis used in providing feedback to the game program to influence the gamestate changes. In this embodiment, any other input data related to thegame program 117 are transmitted by the HMD 104 to the processor and theprocessor 176 interprets the other input data with the six-axis data todetermine if the game state of the game needs to be altered. Based onthe interpretation, the game state of the game is changed. In someembodiments, the input data from the HMD 104 includes real-worldenvironment data captured by the external camera 101 and sent from thecommunications circuit of the HMD 104 to the communications circuit 178of the computer 172. The real-world environment data may be used toinfluence the virtual game scenes rendered at certain portions of thescreen of the HMD 104.

In some embodiments, the HMD 104 is communicatively connected to thecomputer 172 using a wired connection. In such embodiments, the HMD isconfigured to detect a break in the wired connection so as to pause thevirtual game scenes rendered on the screen of the HMD 104. The HMDdetects a break in the communication connection, generates a signalaccordingly and relays the signal to the computer 172 to cause thecomputer 172 to pause the execution of the game program and to store thegame state and game scenes for the session for the game. Power from abattery of the HMD may be used to provide the power for communicatingwith the computer 172 during the break in the communication connection,the status of the connection. The execution of the game program mayresume as soon as the computer 172 gets a signal from the HMD 104 thatthe wired connection has been re-established. In some embodiments, uponresumption of the connection between the HMD and the computer 172, thecomputer 172 may start streaming the game scenes from the point ofdisruption. In another embodiment, the computer 172 may start streamingthe game scenes from a point before the pause (for example, few hundredframes before the pause) caused by the connection disruption so that theuser may get some time to immerse in the game. In this embodiment, thecomputer 172 may allow the user to re-execute portions of the game toallow the user to get into the game. The communication between the HHCand the HMD and the communication between the HHC and the computer 172may follow a wireless communication protocol.

In some embodiments, the HMD 104 may include one or more internalcameras 103 to detect changes in the user's eyes movement. The internalcameras 103 may also be used to identify/authenticate the user beforeproviding access to the game.

Although detailed description is provided regarding a gamingenvironment, it is envisioned that the interfacing can also take placeduring interactive communication with a computer system. The computersystem can be a general computer, with a graphical user interface thatallows user 108 to present and make gestures in space, that controlicons, entry, selection, text, and other commands.

FIGS. 2A-2D illustrate block diagrams of a head mounted display (HMD)104 depicting various views and aspects that are used to communicateprogram related media data to and from the game cloud 102 and/orcomputer. The HMD 104 is configured to display computer generated image(i.e., virtual image) for a game program 117 that is partially or fullyexecuting on a computer 172, and/or that is partially or fully executingon the game cloud by decoding the media data received at the HMD. TheHMD is also configured to code the media data generated or received atthe HMD before transmitting to the computer and/or game cloud forupdating the executing game program. The HMD is also configured todisplay real-world environment images captured from the perspective ofthe user.

FIG. 2A illustrates an exemplary HMD 104 used for generating input dataand for rendering game scenes and real-world environment scenes. Asshown, the HMD 104 is worn by a user 108. The HMD 104 includes one ormore marker elements that assist in the visual tracking of the HMD.Similarly, the HHC 106 (not shown) includes one or more marker elementsthat are similar to the marker elements provided on the HMD. Each markerelement may be a light emitting diode 214, an infrared light 210, acolor, a reflective material, an object with special features orcharacteristics that are easily recognized via image analysis, etc. Forexample, a spherical object 212 may be added to the HMD for easytracking. In addition, the spherical object 212 may also be illuminatedwith LED light, infrared light, or any other type of illumination. Inaddition, the HMD 104 may also include special visual markers (notshown), such as reflective areas of particular geometrical shape, areaswith a particular color (e.g., blue rectangle, etc.), or markings (e.g.,three parallel lines on the surface of the HMD).

In some embodiments, the HMD also includes additional marker elements onthe side and/or back of the HMD (i.e., the part of the HMD touching theback of the head) to further visually track the location of the HMD bydetecting the respective lights or visual markers.

The visual tracking of the HMD may be enabled with different types ofexternal cameras. In some embodiments, the cameras are observationcameras 171 (of FIG. 1D). In one embodiment, the HMD is tracked with astereo camera 402, which is a camera that includes two or more lenseswith separate image sensor for each lens. The separate image sensorenables the stereo camera to capture three-dimensional images of anobject that provide an illusion of depth. The stereo cameras optics aredesigned, in one embodiment, to be set to optical infinity (for example,about 9 meters) to provide the stereoscopic images. Images of the markerelements of the HMD captured by the different lenses of the camera arecompared using triangulation analysis to determine the location of theHMD in the three-dimensional space (for e.g., the calculation of thedepth within the field of play).

In another embodiment, an infrared (IR) camera 404 may be used toanalyze infrared light 210 provided on the HMD. The infrared light isnot visible to the human eye but can be easily detected by the infraredcamera. The HMD may include infrared lights to avoid distraction in theappearance of the HMD. In some environments (e.g., low light or brightlight), it may be easier to track infrared light than other types oflights for detecting location, shape and or features in the HMD. Theinfrared (IR) cameras provide enhanced imaging and thermal imaging of atracking object, such as the HMD. The IR cameras may also be used asinternal cameras to detect user's gaze direction.

In yet another embodiment, a regular camera 405, also referred to hereinas a mono camera because it has only one lens, is used to track thelights or other marker elements in the HMD that are configured forvisual tracking. In order to determine the depth of the HMD within thefield of play with the regular camera, the size of some of the featureson the HMD are analyzed. The smaller the features are, the further awaythe features are supposed to be from the camera of the HMD. In addition,the visual tracking may also be combined with other types of tracking,such as inertial motion tracking, dead reckoning, ultrasoundcommunication between the HMD and the computing device, etc.

The digital camera 402 captures an image of the HMD 104. When the headof the user 108 tilts or moves, position and location of the markerelements changes in a coordinate system. The digital camera captures animage of the marker elements and sends the image to the computer 172. Animage of the marker elements is an example of input data. Position ofthe HMD 104 in a three dimensional space (X, Y, Z) can be determined bythe processor 176 of the computer 172 based on the positions of themarker elements in the images. Further, inertial motion, e.g., yaw,pitch, and roll, etc., of the HMD 104 is determined by the processor 176of the computer 172 based on movement of the marker elements. In thecases where the computer 172 is not available, the image of the markerelements from the digital camera are sent to the processor of the HMD104 and the HMD's processor will determine the position of the HMD usingthe coordinates of the marker elements.

In some embodiments, the digital camera 402 captures an image of the HHC106. When the hand of the user 108 tilts or moves, position and locationof the marker elements on the HHC changes in a co-ordinate system. Thedigital camera captures an image of the marker elements on the HHC andsends the image to the computer 172 or to the processor of the HMD 104.An image of the marker elements on the HHC is an example of input data.Position of the HHC 106 in a three dimensional space (X, Y, Z) can bedetermined by the processor 176 of the computer 172 or by the processorof the HMD 104 by analyzing the positions of the marker elements on theHHC in the image. Moreover, inertial motion, e.g., yaw, pitch, and roll,etc., of the HMD 104 is determined by the processor 176 of the computer172 or the processor of the HMD 104 based on movement of the markerelements of the HHC.

In some embodiments, instead of the HHC 106, a hand of the user 108 maybe tracked by the digital camera and the tracked data may be used todetermine the position of the hand in three dimensional space and theinertial motion of the hand. In some embodiments, an interactive glovemay be used instead of the HHC 106. The glove may include markerelements to track and interpret the motion of the different portions ofthe user's hand wearing the glove.

For more information regarding method for following a marked object,reference may be made to U.S. Patent Application Publication No.2012-0072119, filed on Aug. 15, 2011 and published on Mar. 22, 2012, andU.S. Patent Application Publication No. 2010-0105475, filed on Oct. 27,2008 and published on Apr. 29, 2010, both of which are hereinincorporated by reference.

As shown, one or more pairs of stereo camera 402, one or more infraredcameras 404 and/or one or more mono camera 405 or combinations thereofmay be used to determine the relative position of the HMD and the motionof the HMD provided by user's head motion as well as the controller,including the user's hand wearing a wearable article/device that is usedto provide input data.

The HMD may also be equipped with one or more internal cameras mountedon the inside to capture images related to the user and feed the imagesto the communication module to provide user specific and environmentspecific data to the HMD. The internal camera(s) may be used to identifya user wearing the HMD, which can be used to obtain user profile of theuser. Accordingly, the internal cameras may be configured to engageretinal scanning technique and/or iris scanning technique to scan theuser's retina or irises and use the data from the scanning to generateat least one biometric identity of the user. The user's biometricidentity may be part of the user's profile. The internal cameras alsoinclude a gaze detector algorithm to detect the direction of the user'sgaze and to adjust the image data rendered on a screen of the HMD basedon the detection. In some embodiments, the internal cameras are IRcameras. The gaze detection technology may also be used to authenticatea user. For example, the user may be asked to follow an object renderedon the screen or track a randomly generated letter, object or pattern(for e.g., a circle, a triangle, a rectangle, etc.) that is rendered onthe screen. In some embodiments, verbal or textual commands may beprovided for a user to track a letter, an object or pattern on thescreen and the user authenticated by using the gaze detectiontechnology. The authentication of a user may be used to allow access toa user account, to a game, to certain parts or levels of a game, etc.

FIG. 2B illustrates a user wearing the HMD 104 with the internal cameras109 (103 of FIG. 1D) for detecting the biometric identity of the userand the eye movement of the user.

The internal cameras (109 of FIG. 2B and 103 of FIG. 1D) and theexternal cameras (101 of FIG. 1D) work hand-in-hand to determine thegaze of the user and to relate the gaze to an object in theline-of-sight of the user's gaze. The game processing module of the HMDincludes the software to compute the direction of the user's gaze andcorrelate it to objects within the field of view of the computeddirection.

The HMD includes one or a pair of display screens in front of one oreach eye. The display screen(s) are miniature screens that includecathode ray tubes (CRTs), liquid crystal displays (LCDs), liquid crystalon silicon (LOC) or organic light emitting diodes (OLEDs), to name afew.

FIG. 2C illustrates a block diagram rendition of a simplified HMD usedin various embodiments of the invention. The HMD may include one or moreanchor straps 401 to allow the HMD to fit securely over a user's headand a front face plate 405. The front face plate 405 includes a screenportion with screen disposed on the inside and one or more internalcamera units (109) disposed thereon. In addition to the internal cameraunits (i.e., inside mounted cameras), one or more external camera units(i.e., outside mounted cameras) (not shown) may also be disposed on theHMD to capture real-world environment as seen from the user'sperspective. The external camera units are in addition to observationcamera 171 that are used to detect the motion of the HMD and the HHC.The face plate of the HMD includes a plurality of marker elementsincluding one or more light emitting diodes 210, one or more infraredlights 214 and one or more spherical objects 212, a colored surface, areflective material, objects with special features or characteristicsthat are easily recognized via image analysis, etc. During game play,image of the marker elements on the HMD are captured by the one or moreobservation camera(s) and coordinates data from the captured image areused to determine the location, movement and position of the HMD. Theobservation camera(s) may be connected to the HMD directly or through acomputer 172 and configured to exchange data related to the capturedimage with the HMD and/or with the computer 172. When transmitted to theHMD, the processor within the HMD processes the data to identify thesix-axis data of the HMD and transmits the processed data to thecomputer 172 and/or to the game cloud 102 through the computer 172 (whenpresent) and router, through the router and network, or directly asinput data from the HMD. The input data influences or affects the gamestate of the game program.

The internal cameras 109 detect and track the user's eye movement andgaze. The internal cameras 109 may be used to determine the user's gazedirection for a period of time (for e.g., when the user who was lookingstraight looks down for some period of time), detect a gaze pattern overa period of time (for e.g., when a user follows an object, traces apattern, etc.), and/or detect changes in gaze directions (for e.g.,back-and-forth movement of the eyes, rolling of the eyes—which may be asign of the user experiencing dizziness—especially in a high intensitygame, etc.). The HMD's internal cameras communicate with the HMD'sexternal cameras and with the observation cameras to determineappropriate game-related data for rendering on the screen of the HMD.This communication will enable rendering of the user/environment relateddata alongside or in place of the game-related data on the screen of theHMD, in response to certain triggered events.

FIG. 2D is a block diagram of a communication architecture of an HMD104. The HMD 104 includes some exemplary modules, such as a video audioseparator 254, a video decoder 255, a memory device 256, a WAC 258, astream buffer 259, one or more speakers 260, a battery 261, a user inputcircuit 262, a display screen 266, a microcontroller 268, an audiobuffer 272, an observation digital camera 274, an external digitalcamera 275 an audio codec 276, an internal digital camera 278, a videobuffer 280, a video audio synchronizer 282, a microphone 284, LEDs 285and IR lights 287. The LEDs 285 and IR lights 287 represent the markerelements that are used to track the position of the HMD.

In a number of embodiments, the speakers 260 form an audio circuit. Invarious embodiments, the audio codec 276, the audio buffer 272, and/orthe speakers 260 form an audio circuit. In various embodiments, themicrocontroller 268 is a display circuit that is used for renderingimages on a display screen. Examples of a display screen 266 include anLED screen, a liquid crystal display (LCD) screen, a liquid crystal onsilicon screen, an organic LED (OLED) screen, a plasma screen, etc. Anexample of the external digital camera includes a first eye camera, suchas Playstation Eye® manufactured by Sony Computer Entertainment, Inc.

The microcontroller 268 stores a rendering program 286 and an operatingsystem 288. The rendering program 286 and the operating system 288 arestored in a memory device of the microcontroller 286 and executed by amicroprocessor of the microcontroller 268. An example of microcontroller268 includes a low cost microcontroller that includes a driver, e.g., anLCD driver, that generates a signal to detect elements (for e.g., LCDs,etc.), to provide media data, for displaying on the display screen 266.Another example of the microcontroller includes a GPU and a memorydevice.

In some embodiments, the memory device of the microcontroller is otherthan a flash memory or a random access memory (RAM). For example, memorydevice of the microcontroller is a buffer. In various embodiments,memory device of the microcontroller is Flash or a RAM. Examples of theuser input circuit 262 include a gyroscope, a magnetometer, and anaccelerometer. In some embodiments, the user input circuit 262 alsoincludes a global position system (GPS), compass or any locationtracking devices. An example of the WAC 258 includes a NIC. In someembodiments, the WAC 258 is referred to herein as a communicationscircuit.

A stream of encoded media data is received into the stream buffer 259from the network 110 or the router 152 (FIGS. 1B-1C). It should be notedthat when the router 152 is coupled to the computer 172 (FIG. 1C), datareceived from the computer 172 is stored in a buffer (not shown) of theHMD 250 or in the memory device 256 instead of being stored in thestream buffer 259.

The WAC 258 accesses the stream of encoded media data from the streambuffer 259 received from the computer or the codec 112 and depacketizesthe stream. The WAC 258 also includes a decoder to decode the encodedmedia data.

In embodiments in which the stream of encoded media data is received bythe computer 172 (FIG. 1C) via the router 152 (FIG. 1C), the NIC 174(FIG. 1C) of the computer 172 depacketizes and decodes the stream ofencoded media data to generate decoded data, which is stored in thebuffer (not shown) of the HMD 250.

The decoded data is accessed by the video audio separator 254 from theWAC 258 or from the buffer (not shown). The video audio separator 254separates audio data within the decoded data from video data.

The video audio separator 254 sends the audio data to the audio buffer272 and the video data to the video buffer 280. The video decoder 255decodes, e.g., the video data and/or changes to the video data from adigital form to an analog form to generate analog video signals. Thevideo audio synchronizer 282 synchronizes the video data stored in thevideo buffer 280 with the audio data stored in the audio buffer 272. Forexample, the video audio synchronizer 282 uses a time of playback of thevideo data and the audio data to synchronize the video data with theaudio data.

The audio codec 276 converts the synchronized audio data from a digitalformat into an analog format to generate audio signals and the audiosignals are played back by the speakers 260 to generate sound. Themicrocontroller 268 executes the rendering program 286 to display a gameon the display screen 266 based on the analog video signals that aregenerated by the video decoder 255. In some embodiments, the gamedisplayed on the display screen 266 is displayed synchronous with theplayback of the audio signals.

Moreover, the user 108 (FIGS. 1A-1C) speaks into the microphone 284,which converts sound signals to electrical signals, e.g., audio signals.The audio codec 276 converts the audio signals from an analog format toa digital format to generate audio data, which is stored in the audiobuffer 272. The audio data stored in the audio buffer 272 is an exampleof input data generated based on a sound of the user 108. The audio datamay also include other audio signals generated at the HMD or detected bythe speakers in the HMD. The audio data is accessed by the WAC 258 fromthe audio buffer 272 to send via the network 110 (FIGS. 1A-1C) to thecodec 112 (FIGS. 1A-1C) of the game cloud 102 (FIGS. 1A-1C). Forexample, the WAC 258 packetizes and encodes the audio data accessed fromthe audio buffer 272 to send via the network 110 to the codec 112.

In some embodiments, the audio data is accessed by the WAC 258 from theaudio buffer 272 to send via the router 152 (FIGS. 1A-1C) and thenetwork 110 (FIGS. 1A-1C) to the codec 112 (FIGS. 1A-1C) of the gamecloud 102. For example, the WAC 258 packetizes and encodes the audiodata accessed from the audio buffer 272 to send via the router 152 andthe network 110 to the codec 112.

The internal digital camera 278 (103 of FIG. 1D, 109 of FIG. 2B)captures one or more images of the eye motions of the user 108 (FIGS.1A-1C) to generate image data, which is an example of input datagenerated at the HMD. based on the head and/or eye motions. Similarly,the observation digital camera 274 (camera 171 of FIG. 1D) and/or theexternal digital camera 275 (camera 101 of FIG. 1D) mounted on the HMDcaptures one or more images of markers located on the HMD 250 and/or onthe HHC/glove/hand of the user 108, head motions of the user wearing theHMD, to generate image data, which is an example of input data that isgenerated based on the hand/head motions. The image data captured by thedigital cameras 274, 275 and 278 is stored in the video buffer 280.

In some embodiments, the image data captured by the digital cameras 274,275 and 278 is stored in a buffer of the HMD 250 and the buffer is otherthan the video buffer 280. In various embodiments, the image datacaptured by the digital cameras 274, 275 and 278 is decoded by the videodecoder 255 and sent to the microcontroller 268 for display of images onthe display screen 266.

The image data captured by the digital cameras 274, 275 and 278 isaccessed by the WAC (wireless access card) 258 from the video buffer 280to send via the network 110 (FIGS. 1A-1C) to the codec 112 (FIGS. 1A-1C)of the game cloud 102 (FIGS. 1A-1C, 2). For example, the WAC 258packetizes and encodes the image data accessed from the video buffer 280to send via the network 110 to the codec 112.

In some embodiments, the video data is accessed by the WAC 258 from thevideo buffer 280 to send via the router 152 (FIGS. 1B-1C) and thenetwork 110 (FIGS. 1A-1C) to the codec 112 (FIGS. 1A-1C) of the gamecloud 102. For example, the WAC 258 packetizes and encodes the videodata accessed from the video buffer 280 to send via the router 152and/or the network 110 to the codec 112.

The controller/console communications circuit 289 receives media datafrom the computer 172 for storage in the buffer (not shown). Moreover,the controller/console communications circuit 289 receives input signalsfrom the HHC 106 (FIGS. 1A-1C), converts the input signals from ananalog form to a digital form to generate input data, which is accessedby the WAC 258 to send via the network 110 (FIGS. 1A-1C) to the codec112 (FIGS. 1A-1C) of the game cloud 102 (FIGS. 1A-1C). For example, theWAC 258 packetizes and encodes the input data accessed from thecontroller/console communications circuit 289 to send via the network110 to the codec 112.

In some embodiments, the input data is accessed by the WAC 258 from thecontroller/console communications circuit 289 to send via the router 152(FIGS. 1B-1C) and the network 110 (FIGS. 1A-1C) to the codec 112 (FIGS.1A-1C) of the game cloud 102. For example, the WAC 258 packetizes andencodes the video data accessed from the video buffer 280 to send viathe router 152 and the network 110 to the codec 112.

It should be noted that instead of the controller/console communicationscircuit 289, two separate communications circuits may be used, one forcommunicating, e.g., receiving, sending, etc., data with the computer172 (FIG. 1C) and another for communicating data with the HHC 106 (FIGS.1A-1C).

In a number of embodiments, the decoder is located outside the WAC 258.In various embodiments, the stream buffer 259 is located within the WAC258.

In some embodiments, the HMD 104 excludes the observation digital camera274. In several embodiments, the HMD 104 includes any number ofmicrocontrollers, any number of buffers, and/or any number of memorydevices.

In various embodiments, the HMD 104 includes one or more batteries 261that provide power to components, e.g., the video audio separator 254,the memory device 256, the wireless access card 258, the stream buffer259, the one or more speakers 260, the user input circuit 262, thedisplay screen 266 the microcontroller 268, the audio buffer 272, theexternal digital camera 274, the audio codec 276, the internal digitalcamera 278, the video buffer 280, the video audio synchronizer 282, andthe microphone 284. The one or more batteries 261 are charged with acharger (not shown) that can be plugged into an alternating currentoutlet.

In a number of embodiments, input data and/or media data is referred toherein as interactive media.

In some embodiments, the HMD 104 includes a communications circuit tofacilitate peer-to-peer multichannel communication between local usersvia pairing. For example, the HMD 104 includes a transceiver thatmodulates sound signals received from the microphone 284 and sends themodulated signals via a channel to a transceiver of another HMD (notshown). The transceiver of the other HMD demodulates the signals toprovide to speakers of the other HMD to facilitate communication betweenthe users.

In various embodiments, different channels are used by the transceiverof the HMD 104 to communicate with different other HMDs. For example, achannel over which the modulated signals are sent to a first other HMDis different than a channel over which modulated signals are sent to asecond other HMD.

In some embodiments, the WAC 258, the user input circuit 262, themicrocontroller 268 and the video decoder 255 are integrated in one ormore individual circuit chips. For example, the WAC 258, the videodecoder 255 and the microcontroller 268 are integrated in one circuitchip and the user input circuit 262 is integrated into another circuitchip. As another example, each of the WAC 258, the user input circuit262, the microcontroller 268 and the video decoder 255 is integrated ina separate circuit chip.

The various modules of the HMD are used to determine an occurrence of atrigger event that necessitates a transition action to be performed andperforms the transition at the HMD screen. In some embodiments, themodules within the HMD are collectively termed “Game Processing Module”.The game processing module of HMD detects occurrence of a trigger eventand allows a HMD view to transition between a “non-transparent” mode, a“semi-transparent” mode, a “simulated transparent” mode and a “fullytransparent” mode based on trigger event. In some embodiments, the usermay be provided with options to determine which transparent modetransition is desired by the user and the transition is performed inaccordance to the option chosen. Based on the transition, the user isable to either partially or fully view the real-world environment and/orthe interactive scenes of the game play. It should be noted that whenthe interactive scene from the game is rendered on the screen of theHMD, the screen is said to be in a “non-transparent” mode.

In some embodiments, based on detection of a trigger event, the gameprocessing module transitions the HMD screen from a non-transparent modeto a semi-transparent mode. In some embodiments, the transition from thenon-transparent mode to semi-transparent mode is performed in only aportion of the HMD screen while the remaining portion of the HMD screencontinues to be in non-transparent mode. Alternately, the entire HMDscreen is transitioned from non-transparent mode to semi-transparentmode. In the semi-transparent mode, some objects of the real-worldenvironment are presented with the interactive scene of a game programcurrently rendering on the HMD screen. The real-world environmentpresented at the HMD screen is captured from the immediate vicinity ofthe user, by a forward facing camera of the HMD. The real-worldenvironment, in one embodiment, is presented such that the interactivescene of the game is rendered in the background and some of the objectsfrom the real-world environment are rendered in the foreground.Alternately, in another embodiment, the interactive scene is rendered inthe foreground while some of the objects from the real-world environmentare rendered in the background.

In one embodiment, in response to the occurrence of a trigger event, thegame processing module transitions the HMD screen from a non-transparentmode, where only the interactive scene of the game is being rendered, toa simulated transparent mode, where a user is exposed to a view of thereal-world environment from the user's immediate vicinity. In thisembodiment, the game processing module activates and directs a forwardfacing camera in the HMD to capture and transmit image and/or video ofthe real-world environment that is in line with the user's gaze, fromthe vicinity of the user wearing the HMD. The game processing modulereceives the image/video transmitted by the forward facing camera,processes the image/videos (for e.g., to re-size, re-adjust resolution,etc.), and renders the processed image/videos of the real-worldenvironment on the HMD screen. The rendering causes replacement of theinteractive scenes of the game program currently being rendered with theprocessed image/video. In this embodiment, the simulated transitionmakes it appear that the game processing module has transitioned the HMDscreen to a “fully transparent” mode but, in reality, has provided asimulated transition by presenting an image of the real-worldenvironment captured by the forward facing camera, at the HMD screen.

In another embodiment, the game processing module effectuates thetransition between non-transparent (i.e., opaque or dark) mode and fullytransparent (i.e., clear) mode, in response to detection of a triggerevent, by adjusting optic setting of the HMD screen. In this embodiment,the HMD screen is a liquid crystal display (LCD) screen. The gameprocessing module switches the optic characteristics of the LCD screenbetween dark/black setting (representing non-transparent mode) and clearsetting (representing fully transparent mode). The clear setting enablesthe user to see through the display screen of the HMD at the real-worldobjects from the user's immediate surrounding environment, in a mannerthat is similar to viewing through a clear glass screen. In theopaque/dark setting, the user is unable to or is hard to view throughthe display screen. In the non-transparent mode (i.e., opaque/darksetting), the interactive scenes of the game are rendered in the displayscreen of the HMD. The adjustment of the optic setting for transitioningbetween non-transparent mode to fully transparent mode is done frombehind the LCD screen. Of course, the optics of the LCD screen of theHMD needs to be inverted when facing outwards.

In one embodiment, the trigger event is analyzed to determine if a modetransition is warranted and the mode transitioning is effectuated,including inversion of optics, based on the determination. For example,the analysis may determine if a user's gaze shift is for a period longenough to warrant a transition in mode and the mode transition iseffectuated when the gaze shift is for a period that is at least equalto a pre-defined threshold period. Thus, the game processing moduleprovides alternate ways to transition between non-transparent mode and atransparent mode to allow the user to view the real-world environmenteither partially or fully from time to time, depending on the triggerevents while allowing the user to immerse in the game play experiencetrigger event. The transparent mode may be any one or combination ofsemi-transparent mode, simulated transparent mode and fully transparentmode.

Some exemplary trigger events that cause the transition from thenon-transparent mode to semi-transparent, simulated transparent or fullytransparent mode may include any one or a combination of shift in gazeof a user wearing the HMD, voice command, action detected at the HHC/HMDincluding button press, touch-screen interaction, gesture, interactionthrough one or more input mechanism/device, etc., sound or movementdetected in the immediate surrounding of the user, detecting receipt ofa phone call, text, ping, message, email, detecting action of otherusers in the vicinity of the user, such as voice, etc.

This form of transitioning by manipulating what is being rendered on thescreen allows the user to switch from being in a fully immersed state toa partially immersed or non-immersed state. The transition from thenon-transparent mode to the semi-transparent, simulated transparent orfully transparent mode enables the user to view the real-worldenvironment either partially or fully from time to time while continuingto immerse in the game play. In some other embodiments, the transitionfrom the non-transparent mode to a transparent mode (eithersemi-transparent, simulated transparent or fully transparent) providesthe user with the ability to transition from a fully immersed state to acomplete non-immersed state. In some embodiments, the transitioning fromnon-transparent to transparent mode is provided as an option and theuser may choose or not choose to transition.

The transition is enabled by detecting occurrence of an event during theexecution of the game. The occurrence of an event, for example, may bedetermined by identifying and observing a gaze condition of the user'seyes that is wearing the HMD. The observation of the gaze condition mayinclude detecting a gaze direction of the user for a period of time tosee if the gaze has shifted over time, detecting a gaze pattern over aperiod of time to determine if the user is tracking a pattern, switchingof gaze from a first position to a second position back to firstposition repeatedly, detecting changes in gaze directions to determineif the user is experiencing dizziness, etc. The observation of the gazecondition is correlated with the pre-defined actions provided by theHHC, the HMD, the game cloud and/or computer (if present) in order todetermine if transition has to be performed. The actions provided by theHHC or HMD may also include feedback to the game program, such astactile feedback, audio feedback, etc., in addition to the move actions.The user's gaze condition may be tracked using one or more internalcamera units.

During the tracking, if it is determined that the user's gaze continuesto be on a portion/region on the screen that is rendering interactivescenes for the game that directly correlates with the actions providedby the HMD, the HHC and/or the game program, then the screen continuesto exhibit interactive scenes for the game play streaming from the gameprogram, in a non-transparent mode. FIG. 3A illustrates one suchembodiment, wherein the tracking by the internal cameras detects theuser's gaze to be fixed on the interactive scenes being rendered on thescreen at a gaze angle illustrated by line ‘a’ defined at angle ‘Θ’ froma normal line. In response to this detection, the game processing moduleof the HMD will continue to render interactive scenes related to thegame program streaming from the computer or game cloud that correlateswith the gaze angle, on the screen of the HMD. However, if theinside-mounted camera(s) detects change in gaze condition, for e.g.,shifting in the user's gaze to a different portion of the screen, theinternal camera(s) will detect the change in the gaze condition, i.e.,gaze shift, and determine the angle of gaze shift. Multipleinside-mounted cameras may be used to precisely determine thecoordinates of the gaze shift.

FIG. 3B illustrates the change in gaze condition, (i.e., shifting ofgaze) of the user detected by the internal cameras and the direction ofthe shift. The internal cameras may identify the direction of the gazeshift and the level of gaze shift precisely by capturing multiple imageframes of corresponding scene and feed the information to the gameprocessing module of the HMD. In some embodiments, the images providedby the internal camera(s) may also include time-stamps for each framecaptured by the cameras to enable the game processing module to analyzethe image frames as a function of time to determine the shifting of thegaze of the user. The game processing module computes the angle of theshift by analyzing the gaze point from the captured frames. For example,the first gaze of the user, as illustrated in FIG. 3A, detected by theinternal camera is defined by line ‘a’. As defined earlier, the gameprocessing module determines that the first gaze is at an angle ‘Θ’ fromthe normal line (for e.g., x-axis). The game processing module tracks ashift in the gaze direction and determines the angle of the second gaze,represented by line ‘b’ in FIG. 3B, to be at an angle ‘λ’ from thenormal line and that the gaze has shifted from an upward direction to adownward direction. Consequently, the total angle of shift in the gazeof the user is (Θ+λ). Alternately, the shift in the gaze may continue tobe in the upward direction. In such a case, the total angle of shift inthe gaze of the user may be computed to be (λ−Θ) when the angle ‘λ’ isgreater than the angle ‘Θ’ or (Θ−λ) when the angle ‘Θ’ is greater thanthe angle ‘λ’. This information is used by the game processing modulewithin the HMD to not only determine the shifting of gaze but also toidentify game scene and/or objects of real-world environment in the lineof sight at that angle. Precise computation of the angle of shift may bedone using a triangulation technique by analyzing image frames frommultiple cameras.

In response to detecting a shift in the user's gaze, the inside-mountedcamera(s) may also track the gaze pattern. In some embodiments, the gazepattern may be established by the user tracking an object or letterrendered on the screen. In some embodiments, the gaze pattern may be aback-and-forth movement of the eyes between a first position and asecond position on the screen. The gaze pattern may be determined byanalyzing the line of sight information and the time-stamp informationprovided by the image frames capturing the gaze shift. In someembodiments, the shifting in gaze is significant if the user's eyes haveremained shifted from the original angle for more than a pre-definedthreshold period (for e.g., 0.5 sec, 1, sec, 2 secs, 3 secs, 4 secs,etc.). In one embodiment, based on the analysis of the images and thetime-stamps, the game processing module may determine that the gamepattern has not identified any significant change in the gaze conditionof the user, i.e., shifting of gaze was insignificant (time-wise orangle-wise), temporary (occurred once for less than the predefinedthreshold period) and the user has continued to focus on the portion orregion of the screen that is exhibiting game-related activity. In thisembodiment, the game processing module of the HMD will continue tomaintain the non-transparent mode for the screen and continue to renderthe interactive scenes for the game streamed from the game program.

In some embodiments, based on the analysis of the gaze condition, if thegame processing module establishes a user's gaze shifting to a differentportion of the screen, the game processing module tries to determine ifthe direction of user's shifted gaze correlates to a different area ofthe game. If so, the game processing module may switch the interactivescenes to interactive scenes that correlate with the new portion of thescreen for rendering at the HMD.

In one embodiment illustrated in FIG. 3B, if the gaze patternestablishes that the user's gaze is switching between a first region 302and a second region 304, then the game processing module will determinethe direction of interest for the user, determine an object fromreal-world environment that is aligned with the line of sight andprovide a visual of the object in a corresponding region or portion ofthe screen every time the user's gaze is directed to that portion of thescreen. For example, a user may be involved in a car racing game. As heis playing the game, scenes from the car racing game correlating withthe user's input from the HHC and HMD are rendered on the screen of theHMD. During the game play, the user's gaze may have shifted from lookingstraight ahead at the car racing game scene to looking downward towardthe bottom of the screen. In this case, the game processing module willidentify the shift in gaze, establish a gaze pattern to see if the shiftin gaze is significant (in relation to angle and/or time), and use thisinformation to identify either the real-world object/scene orvirtual-world object/scene aligned in that line of sight.

In one embodiment illustrated in FIG. 3B, it might be determined thatthe object in the line of sight of the shifted gaze may be the HHC inthe user's hand that is providing the input to the HMD. The object inthe line of sight of the shifted gaze may be determined by correlatingthe input data from the internal camera with the data from observationcamera and the external cameras mounted on the HMD to determine theobject of interest that correlates with the angle of the shifted gaze.This information is used by the game processing module to direct theexternal camera of the HMD to capture an image of the HHC in the user'shand(s). In response to the command from the game processing module, theexternal camera of the HMD captures the image of the identified objectand transmits the same to the game processing module, which thenconverts the visual image to digital data and forwards the digital datafor rendering at a corresponding portion of the screen of the HMD. Insome embodiments, the visual image of the object may be adjusted tocorrelate with the interactive scenes of the game. For example, if theobject in the line of view is a controller and the game is aninteractive car racing game, the visual image of a controller (i.e.,real-world object in the line of the shifted gaze of the user) may beadjusted to appear as a car steering wheel.

In one embodiment represented in FIG. 3B, the image (i.e., a visual oradjusted visual) of the HHC held in the user's hand is rendered in thebottom portion of the screen of the HMD, represented by region 304,while the remaining portion of the screen, represented by region 302,continue to render the interactive scenes from the game streaming fromthe computer or the game cloud. As a result, the bottom portion of theHMD screen is considered to have transitioned from a non-transparentmode to a simulated transparent mode while the remaining portions of thescreen continue to render in a non-transparent mode. In someembodiments, the image of the rendered scene/object from the real-worldincludes visual depth to provide a 3-dimensional immersion effect on thescreen.

In the embodiment illustrated in FIG. 3B, for example, the image of theobject is super-imposed over the scene rendered in a part of the bottomportion 304 while allowing the interactive scenes to be visible in theremaining part of the bottom portion. The image of the object isrendered in the foreground in the part. In this example, only a part ofthe bottom portion is considered to have transitioned to simulatedtransparent mode while the remaining part of the bottom portion and therest of the screen continues to render the interactive game scene. Inanother embodiment, the interactive game scene may be presented in theremaining part of the bottom portion in greyed-out format, suggestingthat the bottom portion is in a simulated transparent mode. In yetanother embodiment, the entire bottom portion may be transitioned tosimulated transparent mode and the image of the object of interest(i.e., HHC from the above example) along with the surrounding real-worldobjects captured by the forward facing camera, may be rendered.Alternately, the object may be rendered in the background while theinteractive scenes are rendered in the foreground.

It should be noted that the user's gaze may shift in any direction. As aresult, corresponding portions of the screen of the HMD may transitionfrom non-transparent to transparent mode depending on what is beingrendered on that portion of the screen.

In one embodiment, not all shifts in gaze will result in the transitionfrom a non-transparent mode to transparent mode. For example, the user'sgaze may shift from right side of the screen to the left side of thescreen. In this embodiment, the user's gaze may have shifted in responseto a change in the game based on input from the user provided throughthe HMD or HHC, input from another user (in case of multi-player game),or input from the game. In this embodiment, the left side of the screenmay include interactive game scenes based on the changes in the game. Inone embodiment, when the shift in the user's gaze is detected, the gameprocessing module may determine if the shifting of the user's gazeexceeds a pre-defined threshold limit, such as 3 seconds, for example.When the gaze shift exceeds the threshold limit, the game processingmodule updates the screen of the HMD to render game scenes correspondingto the scenes from the direction of the user's gaze while continuing tomaintain the non-transparency mode of the screen.

As mentioned earlier, the trigger event to transition a portion of thescreen from non-transparent mode to semi-transparent orfully-transparent mode is not restricted to the detection of shifting ofgaze. In one embodiment, the transition event may be triggered inresponse to a movement detected in the real-world, near the user or inthe line-of-sight of the user's camera(s) and/or observation camera. Forexample, the transition may be triggered when a person enters a room inwhich the user is engaged in game play of a game executing on a computeror on the game cloud.

FIG. 3C illustrates one such scenario when user 333 enters the room inwhich user 108 is playing an online game. The screen of the HMD worn byuser 108 during game play is rendering interactive scenes from the gameplay of the game program. When the game processing module detects user333 entering the room, the game processing module alters the scenerendered on the screen of user's HMD to include the image of the user333 entering the room, as shown in the portion 340 b of the HMD screen,while continuing to render the interactive scenes of the game play inthe remaining portion represented by 340 a. In this embodiment, theportion of the screen 340 b that is altered correlates with thedirection of user 333's entrance into the room or appearance in theline-of-sight of the cameras detecting the movement. In someembodiments, the change in the scene provides a three-dimensional viewof a portion of the room where the user 333 entered. In this embodiment,the HMD screen is considered to have transitioned to a semi-transparentmode as the portion 340 b continues to render the interactive scenesalong with the user 333.

Alternately, the transition may be triggered when an object comes in aline-of-sight of the outside-mounted camera of the HMD or the externalcamera(s). FIGS. 3D-3F illustrate one such embodiment. In FIG. 3D, thescreen of the user's HMD is rendering an interactive scene of the gamethe user is playing, at time T₀. At time T₀, an object, (e.g., abouncing ball) has started bouncing up but is outside of the view of thecameras associated with the user's HMD. In this example, the object(i.e., ball) is at a height d₀ from the surface. At time T₁, the ballbounces to a height d₁ and, as a result, comes in the view of at leastone camera associated with the HMD (either the external camera orobservation camera). In response to the detection of the object by atleast one of the cameras, the game processing module may render a3-dimensional image of the ball in the portion of the screen thatcorrelates with the angle/position of the ball's location (distance d1)in the screen as detected by the at least one camera.

Consequently, as illustrated in FIG. 3E, the ball bouncing at height d₁is rendered in the portion or region 304 a of the screen while theremaining portion of the screen continues to render the game-relatedinteractive scene. Similarly, at time T₂, the at least one camera of theHMD detects the ball at a different angle/location as the ball continuesits upward ascent to a distance of d₂ and the game processing moduletranslates the different angle/location of the ball to the correspondinglocation on the screen where to render the image of the ball. FIG. 3Fillustrates the location 304 b where the image of the ball is rendered(the location 304 b may correlate with the height d₂) while theremaining portions of the screen continue to render the interactivescene from the game. When the ball falls down, the movement of the ballin the downward direction is captured till the ball moves out of thecapturing range of the cameras. Thus, FIG. 3D illustrates the scenerendered on the screen of the HMD at time T₀ as well as at time T₅, FIG.3E illustrates the scene with the ball covering a portion 304 a of thescreen at time T₁ (corresponding to ball ascending) as well as at timeT₄ (corresponding to ball descending) and FIG. 3F illustrates the scenewith the ball covering a portion 304 b of the scene at time T₂(corresponding to ball ascending) as well as at time T₃ (correspondingto ball ascending). In this embodiment, the HMD screen is considered tohave transitioned from a non-transparent mode to a simulated transparentmode. In some embodiments, the image of the ball may be rendered in theforeground while the interactive scenes may be rendered in thebackground. Alternately, the image of the ball may be rendered in thebackground while the interactive scenes may be rendered in theforeground. In these embodiments, the HMD screen is considered to havetransitioned from a non-transparent mode to a semi-transparent mode. Thegame processing module, thus, provides a user with a way to completelyimmerse in a game while providing a peek into scenes from the real-worldbased on triggering of external events or based on input from the user,such as gaze shifting, or other such visual cues explicitly orimplicitly provided by the user.

In an alternate embodiment, the HMD screen may transition from anon-transparent mode to a fully transparent mode. In this embodiment, inresponse to the trigger event, the game processing module may adjustoptic characteristics of the HMD screen from a dark/opaque setting(representing a non-transparent mode) to a clear setting (representing afully transparent mode). In the clear setting, the user is provided witha full view of the surrounding real-world environment in the immediatevicinity of the user, as though the user is looking through a clearglass. FIG. 3G illustrates an example of this embodiment, wherein theuser is able to view the real-world objects, such as lamp, table,mirror/screen in the room where the user is using the HMD.

FIGS. 4A-4D illustrate alternate embodiments where the game processingmodule combines the interactive game scenes with three-dimensional scenefrom the real-world to provide a three-dimensional (3D) immersion in thegame while receiving a peek into the real-world. FIG. 4A illustrates athree-dimensional game space of a game that is rendered on the user's108 HMD screen. The game space illustrates the users A, B and C atcertain distance from the user 108 and from each other. The HMD screenillustrated in FIG. 4A is shown to be in a non-transparent mode. FIG. 4Billustrates the game space as the user 108 wearing the HMD walks forwardand as he looks down. The forward movement of the user 108 is reflected,in the three-dimensional game space, by the relative position, angle andlocation of the users A, B and C in relation to the user 108 as well asin relation to each other. Additionally, in response to the user movinghis head downward, the game space has moved downward to reveal anadditional player D as well as an update to the relative location of theusers A, B and C in the game space. The downward movement of the user108's head also results in the rendition of the user's HHC in acorresponding portion 401 of the 3D game space that relates to thelocation of the user's hand in the real-world. The HMD screenillustrated in FIG. 4B is considered to have transitioned to asemi-transparent mode and the trigger event causing such transition maybe the user's movement forward and shift in gaze downward.

FIG. 4C illustrates the view rendered on the screen as the user 108continues to walk forward. The game objects (i.e., users) in theinteractive scene have been updated to render the objects to correlatewith the user's movement. In this embodiment, the interactive scenerendered in the HMD screen shows only one user that is in the relatedgame space (for e.g., user C) that correlates with the distance moved bythe user 108. Additionally, the user's continued gaze shift downwardsfor a period greater than a pre-defined threshold period, will cause thegame processing module to bring into focus at least some part of thereal-world objects, such as table lamp, table, game console, etc.,captured by the external camera. The distance, location, angle, etc., ofobjects in the game space and the objects from the real world arerendered on the screen of the HMD by taking into consideration theuser's forward movement and downward gaze shift as captured by theobservation cameras and the external cameras. Thus, the objects (bothreal and virtual objects) are rendered in a manner that makes theobjects appear closer to the user 108. In the example illustrated inFIG. 4C, the HMD screen is considered to have transitioned fromnon-transparent mode to semi-transparent mode. In some embodiments, thevirtual game objects are faded out to the background and the real-worldobjects are brought into focus (i.e., foreground). In an alternateembodiment, the real-world objects are faded out to the background andthe virtual game objects are brought in focus (i.e., foreground).

In one embodiment, the transition from non-transparent mode tosemi-transparent mode may be initiated at the HMD to provide a safe zoneto a user for watching/interact with content rendered on the displayscreen of the HMD, including game scenes from gameplay. For example, auser who is fully immersed in gameplay of a video game may be movingaround in a room while still engaged in the video gameplay. As a result,the user may get closer to an object, such as a wall, a lamp, a table, achair, a sofa, a bed, a cord, a pet, a person, etc., in the room. Inorder to prevent the user from bumping into the object, from beingtangled in a wire/cord of the HMD, from getting hurt, or from causingdamage to the object, the game processing module in the HMD detects theuser's proximity to the object. In response to the user's movement andactions the system may initiate a transition of the display screen ofthe HMD from non-transparent to semi-transparent mode, e.g., when theuser is coming close to an object. In the semi-transparent mode, thegame processing module blends or brings in the object from thereal-world into the game scene that is being rendered on the displayscreen of the HMD, to indicate to the user the presence and proximity ofthe object in the direction of the user's movement. In one example, thesize and proximity of the object that is rendered in the display screenmay be proportional to the relative proximity of the real-world objectto the user. In one embodiment, the real-world object may be rendered inan outline form represented by dotted lines, as illustrated in FIG. 4C.The outline form may be a gray-out form, a broken line form, an outlineform, a ghost form, a semi-transparent form or a fully viewablepresentation. In one embodiment, in addition to the transition, the gameprocessing module may issue a warning sign to the HMD user when the usermoves too close to an object in the room. The warning sign may be inaudio format, haptic format, visual format, or any combinations thereof.The game processing module, thus, may be used for safety purposeswherein the system allows a user to have enriching viewing experiencewhile preserving the safety of the user and of the objects in theimmediate surrounding environment of the user. In one embodiment, thecamera that is used to capture the real-world object may be a depthsensing camera, a regular RGB camera (providing the three basic colorcomponents—red, blue, green, on three different wires), or an ultrasonicsensor that can identify proximity, depth and distance of an object froma user, or any combinations thereof.

FIG. 4D illustrates the game space rendered on the screen of the HMD ofthe user 108 as the user 108 immerses in a 3D interactive experiencewith the game objects in the game space in the game. In one embodiment,the user interacts with the game objects using controller gloves 335.The controller gloves 335, in one embodiment, are configured to providetactile feedback to a user during game interactions with game objects toprovide a more realistic game experience. In some embodiments, thecontroller gloves include marker elements 335-a, such as LED lights, orother trackable objects/markings, etc., to enable the cameras (externaland observation) to detect the finger/hand motions during interactivegame play. The controller gloves acts as the HHC, in that theycommunicate with the computer and the HMD using wireless communicationprotocol. The communication may also include receiving instruction datathat provides feedback to the gloves. Controller glove is one example ofinteractive object that can be used by a user. Other interactive objectsthat can be used by a user to immerse in 3D interactive experienceinclude clothes, shoes, or other wearable articles of clothing, wearabledevices, or holdable objects. FIG. 4D illustrates the user 108interacting with user B in the game space using the controller gloves335. The game processing module detects the presence of the controllergloves within the game space and transitions the HMD screen fromnon-transparent mode to semi-transparent mode so as to provide an imageof the user's hand within the controller gloves (real-world object) inthe location that correlates with the location of the user B's hand.This transition of the relevant portion of the screen makes it appearthat the user 108 is actually interacting with user B in the 3D space.

In another embodiment, the transition may be triggered in response to asound detected near the user 108 or near the microphone that isintegrated or coupled to the HMD of the user 108. Additionally, thetransition may be triggered by explicit commands, such as voice or otherauditory commands originating from the user, from other users near theuser, from other objects near the user, from applications executing onthe HMD (such as pings, text, email, phone, message, etc.). In responseto the trigger event, the game processing module of the HMD determinesthe direction from which the trigger event occurred using audio sensingtechnology, identify the object or scene that is aligned in that line ofsight and provide a visual of the object or the scene in thecorresponding portion of the screen of the HMD. The screen istransitioned from non-transparent mode to semi-transparent by renderingobjects with the interactive game scenes or simulated transparent modeby replacing interactive game scenes with the image from the real-worldenvironment from the vicinity of the user. The trigger event provides apeek view to the real-world scenario while allowing the user to continueto immerse in the game. The direction of the event that triggers thetransition may be accurately determined using triangulation techniqueusing audio sensing technology and use the information from the audiosensing technology to identify the objects using external cameras andthe observation camera(s). The observation cameras may be able to usethe marker elements, such as LEDs, mounted on the outside surface of theHMD to determine the relative position and direction of the user inrelation to the trigger, such as a person entering the room, a sounddetected near the user/microphone of the HMD, etc. Any portion or regionof the screen of the HMD, such as regions represented by TR1-TR9 in FIG.4E, that correlate with the location/direction of the trigger may betransitioned from non-transparent mode to semi-transparent mode.

In some embodiments, the transition from non-transparent mode totransparent mode (i.e., semi-transparent, simulated transparent or fullytransparent mode) may be done in gradual increments either in a linearfashion or non-linear fashion. The transitioning of a portion of thescreen from non-transparent mode to semi-transparent mode may beperformed using any form of fading and an audio, tactile or other formof feedback may be provided to the user when the transition occurs. Theareas or regions that are transitioned from non-transparent tosemi-transparent may be dynamically set depending on the scene renderedby the HMD, depending on objects held by the user, depending on the gazedirection of a user, depending on audio/motion signals detected ordepending on the environment in which the user is using the HMD. Thetransition of certain portions of the screens in the HMD enables a userto establish a connection between the real-world and the virtual world.Thus, when there is an action in the real-world involving a real-worldphysical object that is related to an action occurring in the virtualworld with a virtual object, the system provides a way of tying togetherthe action in the real-world with the action in the virtual world byallowing the user to see a transparent version of the real-world fromwithin the virtual world. Further, the system may provide a way torender action in the real-world involving a physical object that may notbe tied to the virtual world to provide a real-world awareness to theuser.

In one embodiment, transition from non-transparent mode tosemi-transparent mode may be in response to user's interaction in gameplay of an interactive game. For example, a first user may be engaged ina multi-player game with a second player. In this embodiment, when thefirst player points to an object or region, the game processing moduleis able to detect the direction the first user is pointing, determinethe object or scene in the direction of the pointing, and provide anappropriate view of the object or scene to the second player in asemi-transparent mode. In this embodiment, the object or scene may be anobject/scene in the real-world object/scene. The game processing module,in this embodiment, receives input from the external cameras mounted onthe HMDs of the first and the second players as well as one or moreobservation cameras to track multiple points in space in the directionof the pointing so as to be able to determine the angle between the twoplayers' views to the object and then capture the appropriate 3D imagefor rendering at the HMD of the second player, using the triangulationtechnique. In one embodiment, the view of the object or scene that ispresented to the second player correlates with the second player'sposition and view of the object/scene in the real-world as seen/viewedby the second player.

In some embodiments, the system may detect the user's engagement in acertain portion of the screen and not much engagement in a main portionof the screen, where the actions occurring in the game are currentlybeing rendered. The portion of the screen to which the user's attentionis directed may not have any significant game actions occurring at thistime. In these embodiments, the system may determine that the user'sinterest and focus has shifted from the game and may pause the videogame rendition on the HMD screen. Additionally, the system may send apause signal to the game cloud to pause the execution of the gameprogram. In this embodiment, the game processing module may transitionthe entire screen from a non-transparent mode to a fully-transparentmode by adjusting the optic characteristics of the screen to a clearsetting so as to allow the user to view the real-world objects withinthe environment vicinity of the player. In an alternate embodiment, thegame processing module may transition the entire screen from anon-transparent mode to a simulated transparent mode by capturing imagesof the real-world and replacing the interactive scenes of the game withthe captured images of the real-world. The transition from thenon-transparent mode to fully transparent or simulated transparent modemay be done gradually depending on the intensity of the game play thatwas rendering on the screen of the HMD of the user to allow the user totransition from the virtual environment to the real-world environment.

In one embodiment, the system may detect the shifting of the user'sinterest/focus and provide an option to the user for pausing the game.The option for pausing the game may be provided in the form ofactivation of a button, a voice command, an eye signal, an audiocommand, etc. In addition to providing a pause option, a resume optionmay also be provided to the user to enable the user to access andimmerse in the game from where the user left off when the user selectedthe pause option. The resume option may be provided in forms that aresimilar to or different than the pause option.

In some embodiments, after transitioning from non-transparent mode totransparent mode (for e.g., semi-transparent, fully transparent orsimulated transparent mode), the game processing module may return theportion of the screen to non-transparent mode after expiration of apre-set period of time. In some embodiments, transitioning fromnon-transparent to transparent and back to non-transparent mode may bemade in response to the user actions. For example, when a user gazesback and forth between the main game area and a specific portion of thescreen (such as bottom, left, right, top, etc.), the game processingmodule detects this back and forth movement of the user's gaze toestablish the gaze pattern. Based on the gaze pattern, the gameprocessing module switches the appropriate portion of the screen betweena non-transparent mode and a semi-transparent (where the real-worldscene is presented along with the interactive scenes) or simulatedtransparent mode (where at least part of the objects from the real-worldscene replaces at least a portion of the interactive scenes), in linewith the established gaze pattern of the user. Thus, the bottom portionof the screen may render the HHC in the user's hand when the user's gazeis directed downward and when the user's gaze shifts upward, theinteractive game scene from the game program is rendered, therebyproviding a more realistic transition effect to the user. In oneembodiment, the switching of certain portions of the screen fromnon-transparent to a semi-transparent or simulated transparent mode maybe performed after confirming that the detected shift in the gaze of theuser exceeds a pre-defined threshold value (i.e., the user's gaze hasshifted for at least 3 seconds or 5 seconds).

Alternately, the transition from semi-transparent to non-transparentmode may occur when the event that triggered the transition eitherreturns to a normal or steady state, is no longer available or afterexpiration of a period of time. For example, in the case where thetransition occurred due to a person walking into a room, the transitionback to non-transparent mode may occur when the person leaves the roomor remains on the scene for at least the pre-set period of time definedin the pre-defined threshold value.

In one embodiment, transitioning from a non-transparent mode to a fullytransparent mode may occur when a user who is fully immersed in a highintensity game wants to get to a steady state by opting out of the game.In this case, the transitioning from non-transparent mode to fullytransparent mode may be made in a linear gradual increment to climatizethe user to the change in intensity. During the transitioning, the gameprocessing module may adjust the optic characteristics of the HMD screento gradually move from the opaque/dark setting to clear setting.Alternately, the game processing module may perform transition fromnon-transparent mode to simulated transparent mode by receiving andrendering the real-world scene of the immediate environment of the user.In this embodiment, the game processing module may perform a gradualreplacement of the interactive scenes with the captured images of thereal-world scene, to make it appear that the screen of the HMD hasturned completely transparent. The real-world scene may be captured bythe cameras in response to the opting-out trigger event provided throughuser action.

The gradual change in the images being rendered on the optics screenduring the transition from non-transparent mode to semi-transparent,simulated transparent or fully transparent mode is especially usefulwhen the user is fully immersed in a high-intensity game and theshifting in gaze forces a transition from a high-intensity scene to alow-intensity scene or a static scene of the real-world.

FIG. 5 illustrates method operations for executing a game presented on ascreen of a head mounted display, in one embodiment of the invention.The method begins at operation 510, wherein a game is executed. The gamemay be executed on a computer or may be executed on a game cloud.Interactive scenes of the game are rendered on the screen of the HMD asthe game is executed. The interactive scenes include virtual objects,virtual environments and changes to the virtual objects/environments asthe game progresses. The media data for the interactive scenes arestreamed from the computer or the game cloud.

As the game is progressing, a shift in gaze direction of the userwearing the HMD, is detected, as illustrated in operation 520. One ormore internal cameras available within the HMD may be used to monitorthe gaze direction of the user, during game play and provide images ofthe user's gaze direction to a game processing module of the HMD. Thegame processing module receives the images from the internal cameras anddetects a shift in the gaze direction of the user. The game processingmodule may further analyze the shift in gaze direction to determine ifthe shift is for at least a pre-defined threshold period. When it isdetermined that the gaze shift is for at least the pre-defined thresholdperiod, the game processing module will direct forward facing cameras ofthe HMD to capture real-world images that are in line of the gazedirection.

The game processing module receives the real-world images captured fromthe forward-facing camera of the HMD, as illustrated in operation 530.The real-world images are captured in response to trigger events (suchas shift in gaze). Shift in gaze is one type of trigger event thatcauses the capturing images of real-world environment in the vicinity ofthe user wearing the HMD, and other trigger events may also cause thecapturing of real-world environment images from the immediate vicinityof the user wearing the HMD. In some embodiments, instead of capturingthe images of the real-world environment in the vicinity of the user,the game processing module may identify the game scene that is in thedirection of the user's gaze shift and may provide the same at thescreen of the HMD.

A portion of the screen of the HMD is transitioned to a semi-transparentmode such that the transitioning causes image of at least part of thereal-world object to be presented in a portion of the screen with theinteractive scenes of the game, as illustrated in operation 540. Thetransition may be done in gradual increments. In some embodiments, theimage of the objects from the real-world environment are rendered in theportion of the HMD screen such that real-world environment objects arerendered in the foreground and the interactive scenes are rendered inthe background. In other embodiments, the image of the objects from thereal-world environment are rendered in the portion of the HMD screensuch that real-world environment objects are rendered in the backgroundand the interactive scenes are rendered in the foreground. Thetransparent mode may be discontinued after a period of time, asillustrated in operation 550. The discontinuation of the transparentmode causes the HMD screen to switch to non-transparent mode wherein theinteractive scenes of the game are rendered in the HMD screen. Theswitching to non-transparent mode allows the user to fully immerse inthe game while the transition into the transparent mode provides a peekinto the real-world as the user continues to immerse in the game.

FIG. 6 illustrates hardware and user interfaces that may be used toimplement some embodiments of the invention. FIG. 6 schematicallyillustrates the overall system architecture of the Sony® PlayStation 3®entertainment device. Other versions of PlayStation may include more orless features. A system unit 1300 is provided, with various peripheraldevices connectable to the system unit 1300. The system unit 1300includes: a Cell processor 1302; a Rambus® dynamic random access memory(XDRAM) unit 1304; a Reality Synthesizer graphics unit 1306 with adedicated video random access memory (VRAM) unit 1308; and an I/O bridge1310. The system unit 1300 also comprises a Blu Ray® Disk BD-ROM®optical disk reader 1312 for reading from a disk 1312 a and a removableslot-in hard disk drive (HDD) 1314, accessible through the I/O bridge1310. Optionally, the system unit 1300 also comprises a memory cardreader 1301 for reading compact flash memory cards, Memory Stick® memorycards and the like, which is similarly accessible through the I/O bridge1310.

The I/O bridge 1310 also connects to six Universal Serial Bus (USB) 2.0ports 1316; a gigabit Ethernet port 1318; an IEEE 802.11b/g wirelessnetwork (Wi-Fi) port 1320; and a Bluetooth® wireless link port 1322capable of supporting of up to seven Bluetooth connections.

In operation, the I/O bridge 1310 handles all wireless, USB and Ethernetdata, including data from one or more game controllers 110 and 1324. Forexample, when a user is playing a game, the I/O bridge 1310 receivesdata from the game controller 110 and 1324 via a Bluetooth link anddirects it to the Cell processor 1302, which updates the current stateof the game accordingly.

The wireless, USB and Ethernet ports also provide connectivity for otherperipheral devices in addition to game controllers 110 and 1324, suchas: a remote control 1326; a keyboard 1328; a mouse 1330; a portableentertainment device 1332 such as a Sony PSP® entertainment device; avideo camera such as a PlayStation® Eye Camera 1334; a shape object1336; and a microphone 1338. Such peripheral devices may therefore inprinciple be connected to the system unit 1300 wirelessly; for example,the portable entertainment device 1332 may communicate via a Wi-Fiad-hoc connection, while the shape object 1336 may communicate via aBluetooth link.

The provision of these interfaces means that the PlayStation 3 device isalso potentially compatible with other peripheral devices such asdigital video recorders (DVRs), set-top boxes, digital cameras, portablemedia players, Voice over Internet Protocol (IP) telephones, mobiletelephones, printers and scanners. In addition, a legacy memory cardreader 1340 may be connected to the system unit via a USB port 1316,enabling the reading of memory cards of the kind used by thePlayStation® or PlayStation 2® devices.

The game controllers 110 and 1324 are operable to communicate wirelesslywith the system unit 1300 via the Bluetooth link, or to be connected toa USB port, thereby also providing power by which to charge the batteryof the game controllers 110 and 1324. Game controllers 110 and 1324 canalso include memory, a processor, a memory card reader, permanent memorysuch as flash memory, light emitters such as an illuminated sphericalsection, light emitting diodes (LEDs), or infrared lights, microphoneand speaker for ultrasound communications, an acoustic chamber, adigital camera, an internal clock, a recognizable shape facing the gameconsole, and wireless communications using protocols such as Bluetooth®,WiFi™, etc. The recognizable shape can be in a shape substantially of asphere, a cube, parallelogram, a rectangular parallelepiped, a cone, apyramid, a soccer ball, a football or rugby ball, an imperfect sphere, asection of a sphere, a truncated pyramid, a truncated cone, a baseballbat, a truncated cube, a polyhedron, a star, etc., or a combination oftwo of more of these shapes.

Game controller 1324 is a controller designed to be used with two hands,and game controller 110 is a single-hand controller with a ballattachment. In addition to one or more analog joysticks and conventionalcontrol buttons, the game controller is susceptible to three-dimensionallocation determination. Consequently gestures and movements by the userof the game controller may be translated as inputs to a game in additionto or instead of conventional button or joystick commands. Optionally,other wirelessly enabled peripheral devices such as the Sony PSP®portable device may be used as a controller. In the case of the SonyPSP® portable device, additional game or control information (forexample, control instructions or number of lives) may be provided on thescreen of the device. Other alternative or supplementary control devicesmay also be used, such as a dance mat (not shown), a light gun (notshown), a steering wheel and pedals (not shown) or bespoke controllers,such as a single or several large buttons for a rapid-response quiz game(also not shown).

The remote control 1326 is also operable to communicate wirelessly withthe system unit 1300 via a Bluetooth link. The remote control 1326comprises controls suitable for the operation of the Blu Ray™ DiskBD-ROM reader 1312 and for the navigation of disk content.

The Blu Ray™ Disk BD-ROM reader 1312 is operable to read CD-ROMscompatible with the PlayStation and PlayStation 2 devices, in additionto conventional pre-recorded and recordable CDs, and so-called SuperAudio CDs. The reader 1312 is also operable to read DVD-ROMs compatiblewith the Playstation 2 and PlayStation 3 devices, in addition toconventional pre-recorded and recordable DVDs. The reader 1312 isfurther operable to read BD-ROMs compatible with the PlayStation 3device, as well as conventional pre-recorded and recordable Blu-RayDisks.

The system unit 1300 is operable to supply audio and video, eithergenerated or decoded by the PlayStation 3 device via the RealitySynthesizer graphics unit (RSX) 1306, through audio and video connectorsto a display and sound output device 1342 such as a monitor ortelevision set having a display 1346 and one or more loudspeakers 1348,or stand-alone speakers 1350. In one embodiment, voice and gaze inputsare utilized to play sound toward specific audio speakers according tothe POG of the user. The audio connectors 1358 may include conventionalanalogue and digital outputs while the video connectors 1360 mayvariously include component video, S-video, composite video and one ormore High Definition Multimedia Interface (HDMI) outputs. Consequently,video output may be in formats such as PAL or NTSC, or in 720p, 1080i or1080p high definition.

Audio processing (generation, decoding and so on) is performed by theCell processor 1302. The PlayStation 3 device's operating systemsupports Dolby® 5.1 surround sound, Dolby® Theatre Surround (DTS), andthe decoding of 7.1 surround sound from Blu-Ray® disks.

In the present embodiment, the video camera 1334 comprises a singleCharge Coupled Device (CCD), an LED indicator, and hardware-basedreal-time data compression and encoding apparatus so that compressedvideo data may be transmitted in an appropriate format such as anintra-image based MPEG (motion picture expert group) standard fordecoding by the system unit 1300. The camera LED indicator is arrangedto illuminate in response to appropriate control data from the systemunit 1300, for example to signify adverse lighting conditions.Embodiments of the video camera 1334 may variously connect to the systemunit 1300 via a USB, Bluetooth or Wi-Fi communication port. Embodimentsof the video camera may include one or more associated microphones andalso be capable of transmitting audio data. In embodiments of the videocamera, the CCD may have a resolution suitable for high-definition videocapture. In use, images captured by the video camera may, for example,be incorporated within a game or interpreted as game control inputs. Inanother embodiment, the camera is an infrared camera suitable fordetecting infrared light.

In general, in order for successful data communication to occur with aperipheral device such as a video camera or remote control via one ofthe communication ports of the system unit 1300, an appropriate piece ofsoftware such as a device driver should be provided. Device drivertechnology is well-known and will not be described in detail here,except to say that the skilled man will be aware that a device driver orsimilar software interface may be required in the present embodimentdescribed.

FIG. 7 is a block diagram of a Game System 1100, according to variousembodiments of the invention. Game System 1100 is configured to providea video stream to one or more Clients 1110 via a Network 1115. GameSystem 1100 typically includes a Video Server System 1120 and anoptional game server 1125. Video Server System 1120 is configured toprovide the video stream to the one or more Clients 1110 with a minimalquality of service. For example, Video Server System 1120 may receive agame command that changes the state of or a point of view within a videogame, and provide Clients 1110 with an updated video stream reflectingthis change in state with minimal lag time. The Video Server System 1120may be configured to provide the video stream in a wide variety ofalternative video formats, including formats yet to be defined. Further,the video stream may include video frames configured for presentation toa user at a wide variety of frame rates. Typical frame rates are 30frames per second, 60 frames per second, and 1120 frames per second.Although higher or lower frame rates are included in alternativeembodiments of the invention.

Clients 1110, referred to herein individually as 1110A., 1110B., etc.,may include head mounted displays, terminals, personal computers, gameconsoles, tablet computers, telephones, set top boxes, kiosks, wirelessdevices, digital pads, stand-alone devices, handheld game playingdevices, and/or the like. Typically, Clients 1110 are configured toreceive encoded video streams, decode the video streams, and present theresulting video to a user, e.g., a player of a game. The processes ofreceiving encoded video streams and/or decoding the video streamstypically includes storing individual video frames in a receive bufferof the client. The video streams may be presented to the user on adisplay integral to Client 1110 or on a separate device such as amonitor or television. Clients 1110 are optionally configured to supportmore than one game player. For example, a game console may be configuredto support two, three, four or more simultaneous players. Each of theseplayers may receive a separate video stream, or a single video streammay include regions of a frame generated specifically for each player,e.g., generated based on each player's point of view. Clients 1110 areoptionally geographically dispersed. The number of clients included inGame System 1100 may vary widely from one or two to thousands, tens ofthousands, or more. As used herein, the term “game player” is used torefer to a person that plays a game and the term “game playing device”is used to refer to a device used to play a game. In some embodiments,the game playing device may refer to a plurality of computing devicesthat cooperate to deliver a game experience to the user. For example, agame console and an HMD may cooperate with the video server system 1120to deliver a game viewed through the HMD. In one embodiment, the gameconsole receives the video stream from the video server system 1120, andthe game console forwards the video stream, or updates to the videostream, to the HMD for rendering.

Clients 1110 are configured to receive video streams via Network 1115.Network 1115 may be any type of communication network including, atelephone network, the Internet, wireless networks, powerline networks,local area networks, wide area networks, private networks, and/or thelike. In typical embodiments, the video streams are communicated viastandard protocols, such as TCP/IP or UDP/IP. Alternatively, the videostreams are communicated via proprietary standards.

A typical example of Clients 1110 is a personal computer comprising aprocessor, non-volatile memory, a display, decoding logic, networkcommunication capabilities, and input devices. The decoding logic mayinclude hardware, firmware, and/or software stored on a computerreadable medium. Systems for decoding (and encoding) video streams arewell known in the art and vary depending on the particular encodingscheme used.

Clients 1110 may, but are not required to, further include systemsconfigured for modifying received video. For example, a client may beconfigured to perform further rendering, to overlay one video image onanother video image, to crop a video image, and/or the like. Forexample, Clients 1110 may be configured to receive various types ofvideo frames, such as I-frames, P-frames and B-frames, and to processthese frames into images for display to a user. In some embodiments, amember of Clients 1110 is configured to perform further rendering,shading, conversion to 3-D, or like operations on the video stream. Amember of Clients 1110 is optionally configured to receive more than oneaudio or video stream. Input devices of Clients 1110 may include, forexample, a one-hand game controller, a two-hand game controller, agesture recognition system, a gaze recognition system, a voicerecognition system, a keyboard, a joystick, a pointing device, a forcefeedback device, a motion and/or location sensing device, a mouse, atouch screen, a neural interface, a camera, input devices yet to bedeveloped, and/or the like.

The video stream (and optionally audio stream) received by Clients 1110is generated and provided by Video Server System 1120. As is describedfurther elsewhere herein, this video stream includes video frames (andthe audio stream includes audio frames). The video frames are configured(e.g., they include pixel information in an appropriate data structure)to contribute meaningfully to the images displayed to the user. As usedherein, the term “video frames” is used to refer to frames includingpredominantly information that is configured to contribute to, e.g. toeffect, the images shown to the user. Most of the teachings herein withregard to “video frames” can also be applied to “audio frames.”

Clients 1110 are typically configured to receive inputs from a user.These inputs may include game commands configured to change the state ofthe video game or otherwise affect game play. The game commands can bereceived using input devices and/or may be automatically generated bycomputing instructions executing on Clients 1110. The received gamecommands are communicated from Clients 1110 via Network 1115 to VideoServer System 1120 and/or Game Server 1125. For example, in someembodiments, the game commands are communicated to Game Server 1125 viaVideo Server System 1120. In some embodiments, separate copies of thegame commands are communicated from Clients 1110 to Game Server 1125 andVideo Server System 1120. The communication of game commands isoptionally dependent on the identity of the command. Game commands areoptionally communicated from Client 1110A through a different route orcommunication channel that that used to provide audio or video streamsto Client 1110A.

Game Server 1125 is optionally operated by a different entity than VideoServer System 1120. For example, Game Server 1125 may be operated by thepublisher of a multiplayer game. In this example, Video Server System1120 is optionally viewed as a client by Game Server 1125 and optionallyconfigured to appear from the point of view of Game Server 1125 to be aprior art client executing a prior art game engine. Communicationbetween Video Server System 1120 and Game Server 1125 optionally occursvia Network 1115. As such, Game Server 1125 can be a prior artmultiplayer game server that sends game state information to multipleclients, one of which is game server system 1120. Video Server System1120 may be configured to communicate with multiple instances of GameServer 1125 at the same time. For example, Video Server System 1120 canbe configured to provide a plurality of different video games todifferent users. Each of these different video games may be supported bya different Game Server 1125 and/or published by different entities. Insome embodiments, several geographically distributed instances of VideoServer System 1120 are configured to provide game video to a pluralityof different users. Each of these instances of Video Server System 1120may be in communication with the same instance of Game Server 1125.Communication between Video Server System 1120 and one or more GameServer 1125 optionally occurs via a dedicated communication channel. Forexample, Video Server System 1120 may be connected to Game Server 1125via a high bandwidth channel that is dedicated to communication betweenthese two systems.

Video Server System 1120 comprises at least a Video Source 1130, an I/ODevice 1145, a Processor 1150, and non-transitory Storage 1155. VideoServer System 1120 may include one computing device or be distributedamong a plurality of computing devices. These computing devices areoptionally connected via a communications system such as a local areanetwork.

Video Source 1130 is configured to provide a video stream, e.g.,streaming video or a series of video frames that form a moving picture.In some embodiments, Video Source 1130 includes a video game engine andrendering logic. The video game engine is configured to receive gamecommands from a player and to maintain a copy of the state of the videogame based on the received commands. This game state includes theposition of objects in a game environment, as well as typically a pointof view. The game state may also include properties, images, colorsand/or textures of objects. The game state is typically maintained basedon game rules, as well as game commands such as move, turn, attack, setfocus to, interact, use, and/or the like. Part of the game engine isoptionally disposed within Game Server 1125. Game Server 1125 maymaintain a copy of the state of the game based on game commands receivedfrom multiple players using geographically disperse clients. In thesecases, the game state is provided by Game Server 1125 to Video Source1130, wherein a copy of the game state is stored and rendering isperformed. Game Server 1125 may receive game commands directly fromClients 1110 via Network 1115, and/or may receive game commands viaVideo Server System 1120.

Video Source 1130 typically includes rendering logic, e.g., hardware,firmware, and/or software stored on a computer readable medium such asStorage 1155. This rendering logic is configured to create video framesof the video stream based on the game state. All or part of therendering logic is optionally disposed within a graphics processing unit(GPU). Rendering logic typically includes processing stages configuredfor determining the three-dimensional spatial relationships betweenobjects and/or for applying appropriate textures, etc., based on thegame state and viewpoint. The rendering logic produces raw video that isthen usually encoded prior to communication to Clients 1110. Forexample, the raw video may be encoded according to an Adobe Flash®standard, .wav, H.264, H.263, On2, VP6, VC-1, WMA, Huffyuv, Lagarith,MPG-x. Xvid. FFmpeg, x264, VP6-8, realvideo, mp3, or the like. Theencoding process produces a video stream that is optionally packaged fordelivery to a decoder on a remote device. The video stream ischaracterized by a frame size and a frame rate. Typical frame sizesinclude 800×600, 1280×720 (e.g., 720p), 1024×768, although any otherframe sizes may be used. The frame rate is the number of video framesper second. A video stream may include different types of video frames.For example, the H.264 standard includes a “P” frame and a “I” frame.I-frames include information to refresh all macro blocks/pixels on adisplay device, while P-frames include information to refresh a subsetthereof. P-frames are typically smaller in data size than are I-frames.As used herein the term “frame size” is meant to refer to a number ofpixels within a frame. The term “frame data size” is used to refer to anumber of bytes required to store the frame.

In alternative embodiments Video Source 1130 includes a video recordingdevice such as a camera. This camera may be used to generate delayed orlive video that can be included in the video stream of a computer game.The resulting video stream, optionally includes both rendered images andimages recorded using a still or video camera. Video Source 1130 mayalso include storage devices configured to store previously recordedvideo to be included in a video stream. Video Source 1130 may alsoinclude motion or positioning sensing devices configured to detectmotion or position of an object, e.g., person, and logic configured todetermine a game state or produce video-based on the detected motionand/or position.

Video Source 1130 is optionally configured to provide overlaysconfigured to be placed on other video. For example, these overlays mayinclude a command interface, log in instructions, messages to a gameplayer, images of other game players, video feeds of other game players(e.g., webcam video). In embodiments of Client 1110A including a touchscreen interface or a gaze detection interface, the overlay may includea virtual keyboard, joystick, touch pad, and/or the like. In one exampleof an overlay a player's voice is overlaid on an audio stream. VideoSource 1130 optionally further includes one or more audio sources.

In embodiments wherein Video Server System 1120 is configured tomaintain the game state based on input from more than one player, eachplayer may have a different point of view comprising a position anddirection of view. Video Source 1130 is optionally configured to providea separate video stream for each player based on their point of view.Further, Video Source 1130 may be configured to provide a differentframe size, frame data size, and/or encoding to each of Client 1110.Video Source 1130 is optionally configured to provide 3-D video.

I/O Device 1145 is configured for Video Server System 1120 to sendand/or receive information such as video, commands, requests forinformation, a game state, gaze information, device motion, devicelocation, user motion, client identities, player identities, gamecommands, security information, audio, and/or the like. I/O Device 1145typically includes communication hardware such as a network card ormodem. I/O Device 1145 is configured to communicate with Game Server1125, Network 1115, and/or Clients 1110.

Processor 1150 is configured to execute logic, e.g. software, includedwithin the various components of Video Server System 1120 discussedherein. For example, Processor 1150 may be programmed with softwareinstructions in order to perform the functions of Video Source 1130,Game Server 1125, and/or a Client Qualifier 1160. Video Server System1120 optionally includes more than one instance of Processor 1150.Processor 1150 may also be programmed with software instructions inorder to execute commands received by Video Server System 1120, or tocoordinate the operation of the various elements of Game System 1100discussed herein. Processor 1150 may include one or more hardwaredevice. Processor 1150 is an electronic processor.

Storage 1155 includes non-transitory analog and/or digital storagedevices. For example, Storage 1155 may include an analog storage deviceconfigured to store video frames. Storage 1155 may include a computerreadable digital storage, e.g. a hard drive, an optical drive, or solidstate storage. Storage 1115 is configured (e.g. by way of an appropriatedata structure or file system) to store video frames, artificial frames,a video stream including both video frames and artificial frames, audioframe, an audio stream, and/or the like. Storage 1155 is optionallydistributed among a plurality of devices. In some embodiments, Storage1155 is configured to store the software components of Video Source 1130discussed elsewhere herein. These components may be stored in a formatready to be provisioned when needed.

Video Server System 1120 optionally further comprises Client Qualifier1160. Client Qualifier 1160 is configured for remotely determining thecapabilities of a client, such as Clients 1110A or 1110B. Thesecapabilities can include both the capabilities of Client 1110A itself aswell as the capabilities of one or more communication channels betweenClient 1110A and Video Server System 1120. For example, Client Qualifier1160 may be configured to test a communication channel through Network1115.

Client Qualifier 1160 can determine (e.g., discover) the capabilities ofClient 1110A manually or automatically. Manual determination includescommunicating with a user of Client 1110A and asking the user to providecapabilities. For example, in some embodiments, Client Qualifier 1160 isconfigured to display images, text, and/or the like within a browser ofClient 1110A. In one embodiment, Client 1110A is an HMD that includes abrowser. In another embodiment, client 1110A is a game console having abrowser, which may be displayed on the HMD. The displayed objectsrequest that the user enter information such as operating system,processor, video decoder type, type of network connection, displayresolution, etc. of Client 1110A. The information entered by the user iscommunicated back to Client Qualifier 1160.

Automatic determination may occur, for example, by execution of an agenton Client 1110A and/or by sending test video to Client 1110A. The agentmay comprise computing instructions, such as java script, embedded in aweb page or installed as an add-on. The agent is optionally provided byClient Qualifier 1160. In various embodiments, the agent can find outprocessing power of Client 1110A, decoding and display capabilities ofClient 1110A, lag time reliability and bandwidth of communicationchannels between Client 1110A and Video Server System 1120, a displaytype of Client 1110A, firewalls present on Client 1110A, hardware ofClient 1110A, software executing on Client 1110A, registry entrieswithin Client 1110A, and/or the like.

Client Qualifier 1160 includes hardware, firmware, and/or softwarestored on a computer readable medium. Client Qualifier 1160 isoptionally disposed on a computing device separate from one or moreother elements of Video Server System 1120. For example, in someembodiments, Client Qualifier 1160 is configured to determine thecharacteristics of communication channels between Clients 1110 and morethan one instance of Video Server System 1120. In these embodiments theinformation discovered by Client Qualifier can be used to determinewhich instance of Video Server System 1120 is best suited for deliveryof streaming video to one of Clients 1110.

Embodiments of the present invention may be practiced with variouscomputer system configurations including hand-held devices,microprocessor systems, microprocessor-based or programmable consumerelectronics, minicomputers, mainframe computers and the like. Severalembodiments of the present invention can also be practiced indistributed computing environments where tasks are performed by remoteprocessing devices that are linked through a wire-based or wirelessnetwork.

With the above embodiments in mind, it should be understood that anumber of embodiments of the present invention can employ variouscomputer-implemented operations involving data stored in computersystems. These operations are those requiring physical manipulation ofphysical quantities. Any of the operations described herein that formpart of various embodiments of the present invention are useful machineoperations. Several embodiments of the present invention also relates toa device or an apparatus for performing these operations. The apparatuscan be specially constructed for the required purpose, or the apparatuscan be a general-purpose computer selectively activated or configured bya computer program stored in the computer. In particular, variousgeneral-purpose machines can be used with computer programs written inaccordance with the teachings herein, or it may be more convenient toconstruct a more specialized apparatus to perform the requiredoperations.

Various embodiments of the present invention can also be embodied ascomputer readable code on a computer readable medium. The computerreadable medium is any data storage device that can store data, whichcan be thereafter be read by a computer system. Examples of the computerreadable medium include hard drives, network attached storage (NAS),read-only memory (ROM), random-access memory, compact disc-ROMs(CD-ROMs), CD-recordables (CD-Rs), CD-rewritables (RWs), magnetic tapesand other optical and non-optical data storage devices. The computerreadable medium can include computer readable tangible mediumdistributed over a network-coupled computer system so that the computerreadable code is stored and executed in a distributed fashion.

Although the method operations were described in a specific order, itshould be understood that other housekeeping operations may be performedin between operations, or operations may be adjusted so that they occurat slightly different times, or may be distributed in a system whichallows the occurrence of the processing operations at various intervalsassociated with the processing, as long as the processing of the overlayoperations are performed in the desired way.

Although the foregoing invention has been described in some detail forpurposes of clarity of understanding, it will be apparent that certainchanges and modifications can be practiced within the scope of theappended claims. Accordingly, the present embodiments are to beconsidered as illustrative and not restrictive, and the variousembodiments of the present invention is not to be limited to the detailsgiven herein, but may be modified within the scope and equivalents ofthe appended claims.

What is claimed is:
 1. A method for executing an interactive game,comprising: executing the interactive game, wherein the interactive gameis a multi-player game; rendering interactive scenes of the interactivegame on a screen of a first HMD worn by a first user and a screen of asecond HMD worn by a second user, each of the first and the second usersproviding input to influence an outcome of the interactive game, thescreens of the first HMD and the second HMD being operated in anon-transparent mode; detecting an action initiated by the first userwhile the interactive scenes are being rendered on the screens of thefirst HMD and the second HMD, wherein the action of the first user isdirected to a region in a real-world environment in which the first andthe second users are interacting with the interactive game; analyzingthe action to identify an object in the region of the real-worldenvironment toward which the action is directed, the action beinganalyzed using images of the real-world environment captured by one ormore image sensing devices available within the real-world environment;and transitioning a portion of the screen of the second HMD worn by thesecond user from the non-transparent mode to a transparent mode, so asto provide a view of the object in the region, to the second user. 2.The method of claim 1, wherein the action is initiated by the first userin response to a trigger event occurring in a real-world environment inwhich the first and the second users are interacting with theinteractive game, the action used to provide a warning to the seconduser.
 3. The method of claim 1, wherein the analysis is used to identifya location, direction of the region toward which the action is directed,and the images of the region in the real-world environment is used toidentify the object that correlates with the location, direction of theaction.
 4. The method of claim 1, wherein the action initiated by thefirst user is directed toward the second user.
 5. The method of claim 1,wherein the action initiated by the first user is a movement of a hand,an eye, or head toward the region.
 6. The method of claim 1, wherein theaction is provided in response to detecting the second user movingtoward the object that is present in the region of the real-worldenvironment, or the object in the region moving toward the second user,or any combinations thereof.
 7. The method of claim 1, further includesproviding a warning to notify the second user of a proximity of thesecond user to the region in which the object is present.
 8. The methodof claim 1, wherein the view of the object in the region is providedfrom a perspective of the second user captured using one or more camerasof the second HMD worn by the second user.
 9. The method of claim 1,wherein the one or more image sensing devices capturing the images ofthe real-world environment include a pair of cameras mounted on thefirst HMD, or a pair of cameras mounted on the second HMD, or one ormore observation cameras disposed in the real-world environment externalto the first HMD and the second HMD, or any combinations thereof,wherein the pair of cameras on the first HMD, the second HMD and theobservation cameras are depth sensing cameras.
 10. The method of claim1, further includes discontinuing the transparent mode in the portion ofthe second HMD after a pre-defined period of time, the discontinuingcausing the portion of the second HMD to return to the non-transparentmode.
 11. A method for executing an interactive game, comprising:executing the interactive game, wherein the interactive game is amulti-player game; rendering interactive scenes of the interactive gameon a screen of a first HMD worn by a first user and a screen of a secondHMD worn by a second user, each of the first and the second usersproviding input to influence an outcome of the interactive game, thescreens of the first HMD and the second HMD being operated in anon-transparent mode; detecting a trigger event occurring in a region ofthe real-world environment in which the first and the second users areinteracting with the interactive game, wherein the trigger eventinitiates an action from the first user during rendering of theinteractive scenes on the screens of the first HMD and the second HMD;analyzing the action to identify a portion of the screen of the secondHMD for transitioning to a transparent mode, wherein the portion isidentified to correspond with a direction that provides a view of theaction initiated by the first user, the direction identified from imagesof the real-world environment captured by one or more image sensingdevices available within the real-world environment; and transitioningthe portion of the screen of the second HMD worn by the second user fromthe non-transparent mode to the transparent mode, so as to provide theview of the action initiated for the trigger event occurring in theregion, the view is from a perspective of the second user.
 12. Themethod of claim 11, wherein the first user is operating within a firstsub-region of the region in the real-world environment and the seconduser is operating within a second sub-region of the region in thereal-world environment.
 13. The method of claim 12, wherein detectingthe trigger event includes identifying a location in the real-worldenvironment where the trigger event is occurring; and when the action ofthe first user causes the first user to be proximate to the secondsub-region in which the second user is operating, transitioning theportion of the screen of the second HMD of the second user from thenon-transparent mode to the transparent mode to inform the second userof the proximity of the first user.
 14. The method of claim 12, whereindetecting the trigger event includes identifying a location in thereal-world environment where the trigger event is occurring; and whenthe action of the first user causes the first user to enter the secondsub-region in which the second user is operating, transitioning theportion of the screens of the first HMD of the first user and the secondHMD of the second user from the non-transparent mode to the transparentmode, to warn of proximity of the first user to the second user.